I want to convert my code number of my card to QR image, so I added one reference to my project. Then I created one method in my Helper Class :
public static Image GenerateQRCode(String code)
{
QrEncoder qrEncoder = new QrEncoder(ErrorCorrectionLevel.H);
QrCode qrCode = new QrCode();
qrEncoder.TryEncode(code, out qrCode);
Renderer renderer = new Renderer(5, Brushes.Black, Brushes.White);
MemoryStream ms = new MemoryStream();
renderer.WriteToStream(qrCode.Matrix, ms, System.Drawing.Imaging.ImageFormat.Png);
return System.Drawing.Image.FromStream(ms);
}
And then I call this function in my view :
<%
System.Drawing.Image image = ICEWeb.HelperClasses.HelperClass.GenerateQRCode("test");
%>
But it display only System.Drawing.Bitmap, Does anyone knwo how to display the System.Drawing.Image that return from my function GenerateQRCode() ?
Thna
Do it MVCishly: by writing a custom action result. The GenerateQRCode method that you currently have is something that you could leave behind in the legacy application where it was taken from.
public class QRCodeResult : ActionResult
{
public QRCodeResult(string code)
{
Code = code;
}
public string Code { get; private set; }
public override void ExecuteResult(ControllerContext context)
{
var response = context.HttpContext.Response;
response.ContentType = "image/png";
QrEncoder qrEncoder = new QrEncoder(ErrorCorrectionLevel.H);
QrCode qrCode = new QrCode();
qrEncoder.TryEncode(Code, out qrCode);
Renderer renderer = new Renderer(5, Brushes.Black, Brushes.White);
renderer.WriteToStream(qrCode.Matrix, response.OutputStream, System.Drawing.Imaging.ImageFormat.Png);
}
}
and then a controller action:
public ActionResult QRCode(string code)
{
return new QRCodeResult(code);
}
and finally in some view where you want to display the QR code use an <img> tag pointing to the controller action you wrote:
<img src="<%: Url.Action("QRCode", new { code = "test" }) %>" alt="" />
Related
I am using iText7 to build a table of contents for my document. I know all the section names before I start, but don't know what the page numbers will be. My current process is to create a table on the first page and create all the Link objects with generic text "GO!". Then as I add sections I add through the link objects and update the text with the page numbers that I figured out as I created the document.
However, at the end, what gets written out for the link is "GO!", not the updated page number values I set as I was creating the rest of the document.
I did set the immediateFlush flag to false when I created the Document.
public class UpdateLinkTest {
PdfDocument pdfDocument = null;
List<Link>links = null;
Color hyperlinkColor = new DeviceRgb(0, 102, 204);
public static void main(String[] args) throws Exception {
List<String[]>notes = new ArrayList<>();
notes.add(new String[] {"me", "title", "this is my text" });
notes.add(new String[] {"me2", "title2", "this is my text 2" });
new UpdateLinkTest().exportPdf(notes, new File("./test2.pdf"));
}
public void exportPdf(List<String[]> notes, File selectedFile) throws Exception {
PdfWriter pdfWriter = new PdfWriter(selectedFile);
pdfDocument = new PdfDocument(pdfWriter);
Document document = new Document(pdfDocument, PageSize.A4, false);
// add the table of contents table
addSummaryTable(notes, document);
// add a page break
document.add(new AreaBreak(AreaBreakType.NEXT_PAGE));
// add the body of the document
addNotesText(notes, document);
document.close();
}
private void addSummaryTable(List<String[]> notes, Document document) {
links = new ArrayList<>();
Table table = new Table(3);
float pageWidth = PageSize.A4.getWidth();
table.setWidth(pageWidth-document.getLeftMargin()*2);
// add header
addCell("Author", table, true);
addCell("Title", table, true);
addCell("Page", table, true);
int count = 0;
for (String[] note : notes) {
addCell(note[0], table, false);
addCell(note[1], table, false);
Link link = new Link("Go!", PdfAction.createGoTo(""+ (count+1)));
links.add(link);
addCell(link, hyperlinkColor, table, false);
count++;
}
document.add(table);
}
private void addNotesText(List<String[]> notes, Document document)
throws Exception {
int count = 0;
for (String[] note : notes) {
int numberOfPages = pdfDocument.getNumberOfPages();
Link link = links.get(count);
link.setText(""+(numberOfPages+1));
Paragraph noteText = new Paragraph(note[2]);
document.add(noteText);
noteText.setDestination(++count+"");
if (note != notes.get(notes.size()-1))
document.add(new AreaBreak(AreaBreakType.NEXT_PAGE));
}
}
private static void addCell(String text, Table table, boolean b) {
Cell c1 = new Cell().add(new Paragraph(text));
table.addCell(c1);
}
private static void addCell(Link text, Color backgroundColor, Table table, boolean b) {
Cell c1 = new Cell().add(new Paragraph(text));
text.setUnderline();
text.setFontColor(backgroundColor);
table.addCell(c1);
}
}
Quite more work needs to be done compared to the code you have now because the changes to the elements don't take any effect once you've added them to the document. Immediate flush set to false allows you to relayout the elements, but that does not happen automatically. The way you calculate the current page the paragraph will be placed on (int numberOfPages = pdfDocument.getNumberOfPages();) is not bulletproof because in some cases pages might be added in advance, even if the content is not going to be placed on them immediately.
There is a very low level way to achieve your goal but with the recent version of iText (7.1.15) there is a simpler way as well, which still requires some work though. Basically your use case is very similar to target-counter concept in CSS, with page counter being the target one in your case. To support target counters in pdfHTML add-on we added new capabilities to our layout module which are possible to use directly as well.
To start off, we are going to tie our Link elements to the corresponding Paragraph elements that they will point to. We are going to do it with ID property in layout:
link.setProperty(Property.ID, String.valueOf(count));
noteText.setProperty(Property.ID, String.valueOf(count));
Next up, we are going to create custom renderers for our Link elements and Paragraph elements. Those custom renderers will interact with TargetCounterHandler which is the new capability in layout module I mentioned in the introduction. The idea is that during layout operation the paragraph will remember the page on which it was placed and then the corresponding link element (remember, link elements are connected to paragraph elements) will ask TargetCounterHandler during layout process of that link element which page the corresponding paragraph was planed on. So in a way, TargetCounterHandler is a connector.
Code for custom renderers:
private static class CustomParagraphRenderer extends ParagraphRenderer {
public CustomParagraphRenderer(Paragraph modelElement) {
super(modelElement);
}
#Override
public IRenderer getNextRenderer() {
return new CustomParagraphRenderer((Paragraph) modelElement);
}
#Override
public LayoutResult layout(LayoutContext layoutContext) {
LayoutResult result = super.layout(layoutContext);
TargetCounterHandler.addPageByID(this);
return result;
}
}
private static class CustomLinkRenderer extends LinkRenderer {
public CustomLinkRenderer(Link link) {
super(link);
}
#Override
public LayoutResult layout(LayoutContext layoutContext) {
Integer targetPageNumber = TargetCounterHandler.getPageByID(this, getProperty(Property.ID));
if (targetPageNumber != null) {
setText(String.valueOf(targetPageNumber));
}
return super.layout(layoutContext);
}
#Override
public IRenderer getNextRenderer() {
return new CustomLinkRenderer((Link) getModelElement());
}
}
Don't forget to assign the custom renderers to their elements:
link.setNextRenderer(new CustomLinkRenderer(link));
noteText.setNextRenderer(new CustomParagraphRenderer(noteText));
Now, the other thing we need to do it relayout. You already set immediateFlush to false and this is needed for relayout to work. Relayout is needed because on the first layout loop we will not know all the positions of the paragraphs, but we will already have placed the links on the pages by the time we know those positions. So we need the second pass to use the information about page numbers the paragraphs will reside on and set that information to the links.
Relayout is pretty straightforward - once you've put all the content you just need to call a single dedicated method:
// For now we have to prepare the handler for relayout manually, this is going to be improved
// in future iText versions
((DocumentRenderer)document.getRenderer()).getTargetCounterHandler().prepareHandlerToRelayout();
document.relayout();
One caveat is that for now you also need to subclass the DocumentRenderer since there is an additional operation that needs to be done that is not performed under the hood - propagation of the target counter handler to the root renderer we will be using for the second layout operation:
// For now we have to create a custom renderer for the root document to propagate the
// target counter handler to the renderer that will be used on the second layout process
// This is going to be improved in future iText versions
private static class CustomDocumentRenderer extends DocumentRenderer {
public CustomDocumentRenderer(Document document, boolean immediateFlush) {
super(document, immediateFlush);
}
#Override
public IRenderer getNextRenderer() {
CustomDocumentRenderer renderer = new CustomDocumentRenderer(document, immediateFlush);
renderer.targetCounterHandler = new TargetCounterHandler(targetCounterHandler);
return renderer;
}
}
document.setRenderer(new CustomDocumentRenderer(document, false));
And now we are done. Here is our visual result:
Complete code looks as follows:
public class UpdateLinkTest {
PdfDocument pdfDocument = null;
Color hyperlinkColor = new DeviceRgb(0, 102, 204);
public static void main(String[] args) throws Exception {
List<String[]> notes = new ArrayList<>();
notes.add(new String[] {"me", "title", "this is my text" });
notes.add(new String[] {"me2", "title2", "this is my text 2" });
new UpdateLinkTest().exportPdf(notes, new File("./test2.pdf"));
}
public void exportPdf(List<String[]> notes, File selectedFile) throws Exception {
PdfWriter pdfWriter = new PdfWriter(selectedFile);
pdfDocument = new PdfDocument(pdfWriter);
Document document = new Document(pdfDocument, PageSize.A4, false);
document.setRenderer(new CustomDocumentRenderer(document, false));
// add the table of contents table
addSummaryTable(notes, document);
// add a page break
document.add(new AreaBreak(AreaBreakType.NEXT_PAGE));
// add the body of the document
addNotesText(notes, document);
// For now we have to prepare the handler for relayout manually, this is going to be improved
// in future iText versions
((DocumentRenderer)document.getRenderer()).getTargetCounterHandler().prepareHandlerToRelayout();
document.relayout();
document.close();
}
private void addSummaryTable(List<String[]> notes, Document document) {
Table table = new Table(3);
float pageWidth = PageSize.A4.getWidth();
table.setWidth(pageWidth-document.getLeftMargin()*2);
// add header
addCell("Author", table, true);
addCell("Title", table, true);
addCell("Page", table, true);
int count = 0;
for (String[] note : notes) {
addCell(note[0], table, false);
addCell(note[1], table, false);
Link link = new Link("Go!", PdfAction.createGoTo(""+ (count+1)));
link.setProperty(Property.ID, String.valueOf(count));
link.setNextRenderer(new CustomLinkRenderer(link));
addCell(link, hyperlinkColor, table, false);
count++;
}
document.add(table);
}
private void addNotesText(List<String[]> notes, Document document) {
int count = 0;
for (String[] note : notes) {
Paragraph noteText = new Paragraph(note[2]);
noteText.setProperty(Property.ID, String.valueOf(count));
noteText.setNextRenderer(new CustomParagraphRenderer(noteText));
document.add(noteText);
noteText.setDestination(++count+"");
if (note != notes.get(notes.size()-1))
document.add(new AreaBreak(AreaBreakType.NEXT_PAGE));
}
}
private static void addCell(String text, Table table, boolean b) {
Cell c1 = new Cell().add(new Paragraph(text));
table.addCell(c1);
}
private static void addCell(Link text, Color backgroundColor, Table table, boolean b) {
Cell c1 = new Cell().add(new Paragraph(text));
text.setUnderline();
text.setFontColor(backgroundColor);
table.addCell(c1);
}
private static class CustomLinkRenderer extends LinkRenderer {
public CustomLinkRenderer(Link link) {
super(link);
}
#Override
public LayoutResult layout(LayoutContext layoutContext) {
Integer targetPageNumber = TargetCounterHandler.getPageByID(this, getProperty(Property.ID));
if (targetPageNumber != null) {
setText(String.valueOf(targetPageNumber));
}
return super.layout(layoutContext);
}
#Override
public IRenderer getNextRenderer() {
return new CustomLinkRenderer((Link) getModelElement());
}
}
private static class CustomParagraphRenderer extends ParagraphRenderer {
public CustomParagraphRenderer(Paragraph modelElement) {
super(modelElement);
}
#Override
public IRenderer getNextRenderer() {
return new CustomParagraphRenderer((Paragraph) modelElement);
}
#Override
public LayoutResult layout(LayoutContext layoutContext) {
LayoutResult result = super.layout(layoutContext);
TargetCounterHandler.addPageByID(this);
return result;
}
}
// For now we have to create a custom renderer for the root document to propagate the
// target counter handler to the renderer that will be used on the second layout process
// This is going to be improved in future iText versions
private static class CustomDocumentRenderer extends DocumentRenderer {
public CustomDocumentRenderer(Document document, boolean immediateFlush) {
super(document, immediateFlush);
}
#Override
public IRenderer getNextRenderer() {
CustomDocumentRenderer renderer = new CustomDocumentRenderer(document, immediateFlush);
renderer.targetCounterHandler = new TargetCounterHandler(targetCounterHandler);
return renderer;
}
}
}
So far I can pass the value to the other view but the problem is I don't know how to do this using MVVM. I tried the documentations and tutorial still no luck. How can I achieve this?
The flow of my project:
- The user will login, when the user provides the correct it will return a JSON array that contains the ContactID of the user.
- This ContactID now be pass to the other view. It will be used to synchronize the server to the local database and vice versa
My Questions are:
1. How can I pass the data to other view with MVVM?
2. How can I check if the data is passed correctly?
The Output of the HTTPWebRequest:
[{"ContactID":"1"}]
My Code:
LoginPageViewModel.cs
using Newtonsoft.Json;
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.IO;
using System.Net;
using System.Text;
using System.Windows.Input;
using TBSMobileApplication.Data;
using TBSMobileApplication.View;
using Xamarin.Essentials;
using Xamarin.Forms;
namespace TBSMobileApplication.ViewModel
{
public class LoginPageViewModel : INotifyPropertyChanged
{
void OnPropertyChanged(string PropertyName)
{
PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(PropertyName));
}
public string username;
public string password;
public string Username
{
get { return username; }
set
{
username = value;
OnPropertyChanged(nameof(Username));
}
}
public string Password
{
get { return password; }
set
{
password = value;
OnPropertyChanged(nameof(Password));
}
}
public class LoggedInUser
{
public int ContactID { get; set; }
}
public ICommand LoginCommand { get; set; }
public LoginPageViewModel()
{
LoginCommand = new Command(OnLogin);
}
public void OnLogin()
{
if (string.IsNullOrEmpty(Username) || string.IsNullOrEmpty(Password))
{
MessagingCenter.Send(this, "Login Alert", Username);
}
else
{
var current = Connectivity.NetworkAccess;
if (current == NetworkAccess.Internet)
{
var link = "http://192.168.1.25:7777/TBS/test.php?User=" + Username + "&Password=" + Password;
var request = HttpWebRequest.Create(string.Format(#link));
request.ContentType = "application/json";
request.Method = "GET";
using (HttpWebResponse response = request.GetResponse() as HttpWebResponse)
{
if (response.StatusCode != HttpStatusCode.OK)
{
Console.Out.WriteLine("Error fetching data. Server returned status code: {0}", response.StatusCode);
}
else
{
using (StreamReader reader = new StreamReader(response.GetResponseStream()))
{
var content = reader.ReadToEnd();
if (content.Equals("[]") || string.IsNullOrWhiteSpace(content) || string.IsNullOrEmpty(content))
{
MessagingCenter.Send(this, "Http", Username);
}
else
{
var result = JsonConvert.DeserializeObject<List<LoggedInUser>>(content);
var contactId = result[0].ContactID;
Application.Current.MainPage.Navigation.PushAsync(new DatabaseSyncPage(contactId), true);
}
}
}
}
}
else
{
MessagingCenter.Send(this, "Not Connected", Username);
}
}
}
public event PropertyChangedEventHandler PropertyChanged;
}
}
DatabaseSyncPage.xaml.cs
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Xamarin.Forms;
using Xamarin.Forms.Xaml;
namespace TBSMobileApplication.View
{
[XamlCompilation(XamlCompilationOptions.Compile)]
public partial class DatabaseSyncPage : ContentPage
{
public DatabaseSyncPage (int contanctId)
{
InitializeComponent ();
}
}
}
If you are new to MVVM i would highly recommend using an MVVM helper framework such as Prism, MVVMCross or MVVMLight (there are even more).
I myself use Prism, I believe all of the frameworks are functionally very similar and it comes down more to preference here. I will show you how I pass data between views in my Prism based applications. Before we get started it would be worth to download the prism visual studio extensions and use the template pack to generate a prism project. I use the DryIoc container.
Imagine the scenario where we have ViewA (with ViewAViewModel) and ViewB (with ViewBViewModel). In View A we have an Entry and a Button, when the button is pressed the text from the entry in ViewA is passed to ViewB where it is displayed in a label.
You would first setup your prism project, creating a XAML fronted view for View A & B and then creating 2 class files and creating the relevant View Models (I'll show you how).
Firstly creating the following files:
ViewA (Xaml content page)
ViewB (Xaml content page)
ViewAViewModel (empty class)
ViewBViewModel (empty class)
In your app.cs register the views and view models:
//You must register these views with prism otherwise your app will crash!
protected override void RegisterTypes(IContainerRegistry containerRegistry)
{
containerRegistry.RegisterForNavigation<NavigationPage>();
containerRegistry.RegisterForNavigation<ViewA, ViewAViewModel>();
containerRegistry.RegisterForNavigation<ViewB, ViewBViewModel>();
}
Now format your view models by adding the following:
public class ViewAViewModel : ViewModelBase
{
INavigationService _navigationService;
public ViewAViewModel(INavigationService navigationService) : base(navigationService)
{
Title = "ViewA";
_navigationService = navigationService;
}
}
Repeat the above step for ViewBViewModel also (changing the relevant names).
Now in the views xaml lets add some stuff! Add the following to ViewA.xaml (inside <ContentPage.Content></ContentPage.Content>:
<StackLayout>
<Entry Placeholder="Type Here..." Text="{Binding ViewAText}"/>
<Button Text="Navigate" Command="{Binding OnNavigateCommand}"/>
</StackLayout>
and in ViewB.xaml:
`<Label Text="{Binding TextFromViewA}"/>`
Now I've already added the binding for you, so lets make the properties!
In View Model A add:
private string _viewAText;
public string ViewAText
{
get { return _viewAText; }
set { SetProperty(ref _viewAText, value); }
}
public DelegateCommand OnNavigateCommand { get; set; }
private void OnNavigate()
{
//Do Something
}
Now we have a bindable property and a command for our button press, add the following to the constructor:
public ViewAViewModel(INavigationService navigationService) : base(navigationService)
{
Title = "ViewA";
_navigationService = navigationService;
_viewAText = string.Empty;
OnNavigateCommand = new DelegateCommand(OnNavigate);
}
Now View A can bind text from the entry control and has an event handler for the command!
Lets hop into View B and wire that up!
Add the property:
private string _textFromViewA;
public string TextFromViewA
{
get { return _textFromViewA; }
set { SetProperty(ref _textFromViewA, value); }
}
and in the constructor:
public ViewBViewModel(INavigationService navigationService) : base(navigationService)
{
Title = "ViewB";
TextFromViewA = string.Empty;
}
Now the label we added in ViewB is hooked up to the view model. Lets now pass the text from the entry in A to B!
Back in View A add the following to the OnNavigate method:
private void OnNavigate()
{
NavigationParameters navParams = new NavigationParameters();
navParams.Add("PassedValue", _viewAText);
_navigationService.NavigateAsync("ViewB", navParams);
}
The navigation service is incredibly powerful and allows you to pass a dictionary between views (NavigationParameters). In this code we have created some NavigationParameter, added the value of the text in our entry to them and then asked the navigationService (which handles all navigation from viewmodels in Prism) to navigate to ViewB, passing the parameters to it.
In View B we can listen for these parameters using some built in methods provided by Prism. If you type override in ViewBViewModel you will see the methods:
OnNavigatingTo
OnNavigatedTo
OnNavigatedFrom
In this case we want to use OnNavigatingTo (which is fired during the transition between the views). Pull that method in and the following:
public override void OnNavigatingTo(NavigationParameters parameters)
{
base.OnNavigatingTo(parameters);
if (parameters.ContainsKey("PassedValue"))
{
_textFromViewA = (string)parameters["PassedValue"];
RaisePropertyChanged("TextFromViewA");
}
}
Here we check if the parameters contain the value we added (by searching for the dictionary key) and then retrieve the value (casting it to a string since the dictionary is ). We then set the property the label is bound to = to the passed value and then use a prism method, RaisePropertyChanged() to raise a property changed event so that the label's binded value updates!
Below is a gif of the results!
This might be alot to take in. I would advise you start using an MVVM framework asap, they are really easy to use and I would consider them essential to making testable, decoupled MVVM xamarin apps!
For more on how prism works, I'd suggest to go read the docs and watch Brian Lagunas' appearance on the Xamarin Show!
Good Luck!
i had implemented the same and hope this helps you.
i have create a loginViewModel
public class LoginVerificationVM : BaseViewModel // INotifyPropertyChanged
{
private INavigation _navigation;
private string usermobileno;
public string UserMobileNo
{ get { return usermobileno; }set { usermobileno = value;
OnPropertyChanged("UserMobileNo"); }
}
public LoginVerificationVM(INavigation navigation, string mobileno)
{
UserMobileNo = mobileno;
_navigation = navigation;
}
public Command Login
{
get
{
return new Command(async () =>
{
bool status = await WebApi.CheckNetWorkStatus();
if (status == false)
{
MessageClass.messagesWindow("Check Ur Connectivity");
this.Isvisible = false;
return;
}
Isvisible = true;
UserAuth ud = new UserAuth();
ud.username = UserMobileNo; // UserMobileNo;
ud.password = Password; // Password
ud.grant_type = "password"; //GrantType
Isvisible = true;
// IsBusy = false;
await Task.Delay(100);
var json = Task.Run(() => WebApi.GetUserAuth(ud)).Result;
// IsBusy = false;
if (json.ErrorMessage == "true")
{
Application.Current.MainPage = new MasterPages.MasterPage(json.access_token); //or use _navigation.PushAsync(new ForgotPasswordOTP(UserMobileNo));
}
else
{
MessageClass.messagesWindow(json.ErrorMessage);
}
Isvisible = false;
});
}
}
}
Xaml Code
<Entry x:Name="PasswordEntry" Grid.Row="2" IsPassword="True" Placeholder="******" HorizontalTextAlignment="Center" FontAttributes="Bold" TextColor="Black" WidthRequest="150" HeightRequest="35" FontSize="13" Text="{Binding Password, Mode=TwoWay}" >
<Button x:Name="Login" Grid.Row="3" HorizontalOptions="Center" BorderRadius="8" Text="Login" WidthRequest="100" BackgroundColor="#f7941d" TextColor="White" Command="{Binding Login}" IsEnabled="{Binding Active,Mode=TwoWay}">
here is implementation to get data on navigated page view model
public ForgotPasswordOTP(string Ph)
{
InitializeComponent();
BindingContext = new ForgotPasswordOTPViewModel(this.Navigation,Ph);
}
and the last thing you need to do is bind your view with your viewmodel
** BindingContext = new LoginVerificationVM(this.Navigation);**
And the answer for the last question is you need to deserialize json in c#
which can be done in following way
var userData = JsonConvert.DeserializeObject<YourObject>(result);
I have used a custom image component which has image field-type ribbon when editing in page editor.
In core db, there are 3 webedit buttons for image which I need to hide/disable:
path: /sitecore/system/Field types/Simple Types/Image/WebEdit Buttons/
buttons:
1. Choose Image
2. Image Properties
3. Clear Image
Also, i am aware that this is possible by overriding Querystate() method but im unsure of its implementation as I am new to CommandState handling.
Instead of going through QueryState , I am trying this
I have set the property "DisableEdit" of image as:
<myImage:PictureFillImage Field="<%# MyImage.Constants.FieldNames.Image %>" DisableEdit="true" ID="UIImage" runat="server"/>
I am using a custom class as:
public class PictureFillImage : Sitecore.Web.UI.WebControls.FieldControl
And i am trying to disable web editing for the image as:
public bool DisableEdit { get; set; }
private Sitecore.Web.UI.WebControls.Image _smlImage;
private Sitecore.Data.Fields.ImageField _smlImageField;
private Sitecore.Web.UI.WebControls.FieldControl _fieldControl;
protected override void OnLoad(EventArgs e)
{
this.DataBind();
}
public override void DataBind()
{
// base.OnLoad(e);
this.Item = this.GetItem();
if ((this.Item != null) && (this.Field != null))
{
Sitecore.Data.Fields.Field field = this.Item.Fields[this.Field];
if (field != null)
{
this._smlImageField = (Sitecore.Data.Fields.ImageField)field;
this._smlImage = new Sitecore.Web.UI.WebControls.Image();
this._smlImage.Field = this.Field;
this._fieldControl = this._smlImage as Sitecore.Web.UI.WebControls.FieldControl;
this._smlImage.ID = this.ID;
this._smlImage.CssClass = this.CssClass;
this._smlImage.Parameters = "all=all";
this._fieldControl.Item = this.Item;
this._smlImage.DisableWebEditing = DisableEdit;
this._fieldControl.DisableWebEditing = DisableEdit;
}
}
base.DataBind();
}
I was hoping that the code would hide the three buttons: "Choose Image", "Image Properties" and "Clear Image" that appear in the floating ribbon in the page editor but I had negative result.
Please help.
You should override the query state method and return hidden or enabled
public override CommandState QueryState(CommandContext context)
{
// your logic here
//access current item
var item = context.Items[0];
// return either Commandstate.Hidden or Commandstate.Enabled
}
For each button you will have a command class declared so you can customize the behaviour for each button.
You can get access to the current item as well.
There's a good example here on how to overrride the querystate to affect the state of the buttons
https://briancaos.wordpress.com/2010/09/10/unlock-sitecore-items/
I would like to create a function in C# that takes a specific webpage and coverts it to a JPG image from within ASP.NET. I don't want to do this via a third party or thumbnail service as I need the full image. I assume I would need to somehow leverage the webbrowser control from within ASP.NET but I just can't see where to get started. Does anyone have examples?
Ok, this was rather easy when I combined several different solutions:
These solutions gave me a thread-safe way to use the WebBrowser from ASP.NET:
http://www.beansoftware.com/ASP.NET-Tutorials/Get-Web-Site-Thumbnail-Image.aspx
http://www.eggheadcafe.com/tutorials/aspnet/b7cce396-e2b3-42d7-9571-cdc4eb38f3c1/build-a-selfcaching-asp.aspx
This solution gave me a way to convert BMP to JPG:
Bmp to jpg/png in C#
I simply adapted the code and put the following into a .cs:
using System.Drawing;
using System.Drawing.Imaging;
using System.IO;
using System.Threading;
using System.Windows.Forms;
public class WebsiteToImage
{
private Bitmap m_Bitmap;
private string m_Url;
private string m_FileName = string.Empty;
public WebsiteToImage(string url)
{
// Without file
m_Url = url;
}
public WebsiteToImage(string url, string fileName)
{
// With file
m_Url = url;
m_FileName = fileName;
}
public Bitmap Generate()
{
// Thread
var m_thread = new Thread(_Generate);
m_thread.SetApartmentState(ApartmentState.STA);
m_thread.Start();
m_thread.Join();
return m_Bitmap;
}
private void _Generate()
{
var browser = new WebBrowser { ScrollBarsEnabled = false };
browser.Navigate(m_Url);
browser.DocumentCompleted += WebBrowser_DocumentCompleted;
while (browser.ReadyState != WebBrowserReadyState.Complete)
{
Application.DoEvents();
}
browser.Dispose();
}
private void WebBrowser_DocumentCompleted(object sender, WebBrowserDocumentCompletedEventArgs e)
{
// Capture
var browser = (WebBrowser)sender;
browser.ClientSize = new Size(browser.Document.Body.ScrollRectangle.Width, browser.Document.Body.ScrollRectangle.Bottom);
browser.ScrollBarsEnabled = false;
m_Bitmap = new Bitmap(browser.Document.Body.ScrollRectangle.Width, browser.Document.Body.ScrollRectangle.Bottom);
browser.BringToFront();
browser.DrawToBitmap(m_Bitmap, browser.Bounds);
// Save as file?
if (m_FileName.Length > 0)
{
// Save
m_Bitmap.SaveJPG100(m_FileName);
}
}
}
public static class BitmapExtensions
{
public static void SaveJPG100(this Bitmap bmp, string filename)
{
var encoderParameters = new EncoderParameters(1);
encoderParameters.Param[0] = new EncoderParameter(System.Drawing.Imaging.Encoder.Quality, 100L);
bmp.Save(filename, GetEncoder(ImageFormat.Jpeg), encoderParameters);
}
public static void SaveJPG100(this Bitmap bmp, Stream stream)
{
var encoderParameters = new EncoderParameters(1);
encoderParameters.Param[0] = new EncoderParameter(System.Drawing.Imaging.Encoder.Quality, 100L);
bmp.Save(stream, GetEncoder(ImageFormat.Jpeg), encoderParameters);
}
public static ImageCodecInfo GetEncoder(ImageFormat format)
{
var codecs = ImageCodecInfo.GetImageDecoders();
foreach (var codec in codecs)
{
if (codec.FormatID == format.Guid)
{
return codec;
}
}
// Return
return null;
}
}
And can call it as follows:
WebsiteToImage websiteToImage = new WebsiteToImage( "http://www.cnn.com", #"C:\Some Folder\Test.jpg");
websiteToImage.Generate();
It works with both a file and a stream. Make sure you add a reference to System.Windows.Forms to your ASP.NET project. I hope this helps.
UPDATE: I've updated the code to include the ability to capture the full page and not require any special settings to capture only a part of it.
Good solution by Mr Cat Man Do.
I've needed to add a row to suppress some errors that came up in some webpages
(with the help of an awesome colleague of mine)
private void _Generate()
{
var browser = new WebBrowser { ScrollBarsEnabled = false };
browser.ScriptErrorsSuppressed = true; // <--
browser.Navigate(m_Url);
browser.DocumentCompleted += WebBrowser_DocumentCompleted;
}
...
Thanks Mr Do
Here is my implementation using extension methods and task factory instead thread:
/// <summary>
/// Convert url to bitmap byte array
/// </summary>
/// <param name="url">Url to browse</param>
/// <param name="width">width of page (if page contains frame, you need to pass this params)</param>
/// <param name="height">heigth of page (if page contains frame, you need to pass this params)</param>
/// <param name="htmlToManipulate">function to manipulate dom</param>
/// <param name="timeout">in milliseconds, how long can you wait for page response?</param>
/// <returns>bitmap byte[]</returns>
/// <example>
/// byte[] img = new Uri("http://www.uol.com.br").ToImage();
/// </example>
public static byte[] ToImage(this Uri url, int? width = null, int? height = null, Action<HtmlDocument> htmlToManipulate = null, int timeout = -1)
{
byte[] toReturn = null;
Task tsk = Task.Factory.StartNew(() =>
{
WebBrowser browser = new WebBrowser() { ScrollBarsEnabled = false };
browser.Navigate(url);
browser.DocumentCompleted += (s, e) =>
{
var browserSender = (WebBrowser)s;
if (browserSender.ReadyState == WebBrowserReadyState.Complete)
{
if (htmlToManipulate != null) htmlToManipulate(browserSender.Document);
browserSender.ClientSize = new Size(width ?? browser.Document.Body.ScrollRectangle.Width, height ?? browser.Document.Body.ScrollRectangle.Bottom);
browserSender.ScrollBarsEnabled = false;
browserSender.BringToFront();
using (Bitmap bmp = new Bitmap(browserSender.Document.Body.ScrollRectangle.Width, browserSender.Document.Body.ScrollRectangle.Bottom))
{
browserSender.DrawToBitmap(bmp, browserSender.Bounds);
toReturn = (byte[])new ImageConverter().ConvertTo(bmp, typeof(byte[]));
}
}
};
while (browser.ReadyState != WebBrowserReadyState.Complete)
{
Application.DoEvents();
}
browser.Dispose();
}, CancellationToken.None, TaskCreationOptions.None, TaskScheduler.FromCurrentSynchronizationContext());
tsk.Wait(timeout);
return toReturn;
}
There is a good article by Peter Bromberg on this subject here. His solution seems to do what you need...
The solution is perfect, just needs a fixation in the line which sets the WIDTH of the image. For pages with a LARGE HEIGHT, it does not set the WIDTH appropriately:
//browser.ClientSize = new Size(browser.Document.Body.ScrollRectangle.Width, browser.Document.Body.ScrollRectangle.Bottom);
browser.ClientSize = new Size(1000, browser.Document.Body.ScrollRectangle.Bottom);
And for adding a reference to System.Windows.Forms, you should do it in .NET-tab of ADD REFERENCE instead of COM -tab.
You could use WatiN to open a new browser, then capture the screen and crop it appropriately.
In my ASP.NET MVC 2 application I use HandleErrorAttribute to display a custom error page in case of unhandled exceptions, and it works perfectly unless the exception happens in an action called by Ajax.ActionLink. In this case nothing happens. Is it possible to use HandleErrorAttribute to update the target element with the contents of an "Error.ascx" partial view?
To achieve this you could write a custom action filter:
public class AjaxAwareHandleErrorAttribute : HandleErrorAttribute
{
public string PartialViewName { get; set; }
public override void OnException(ExceptionContext filterContext)
{
// Execute the normal exception handling routine
base.OnException(filterContext);
// Verify if AJAX request
if (filterContext.HttpContext.Request.IsAjaxRequest())
{
// Use partial view in case of AJAX request
var result = new PartialViewResult();
result.ViewName = PartialViewName;
filterContext.Result = result;
}
}
}
And then specify the partial view to be used:
[AjaxAwareHandleError(PartialViewName = "~/views/shared/error.ascx")]
public class HomeController : Controller
{
public ActionResult Index()
{
return View();
}
public ActionResult SomeAction()
{
throw new Exception("shouldn't have called me");
}
}
And finally in your view assuming you have the following link:
<%= Ajax.ActionLink("some text", "someAction", new AjaxOptions {
UpdateTargetId = "result", OnFailure = "handleFailure" }) %>
You could make the handleFailure function to update the proper div:
<script type="text/javascript">
function handleFailure(xhr) {
// get the error text returned by the partial
var error = xhr.get_response().get_responseData();
// place the error text somewhere in the DOM
document.getElementById('error').innerHTML = error;
}
</script>