I have a requirement where excel file ( i will treat this is an a template) which has a pre populated formulas ( for close to 10k rows), when i populate the dependent column values the formulas calculations are not updated or refreshed. please help me with the same.
The formulas will be populated for 10k rows but while populating the data i may be populating the data just for 100 rows but user can add many more records later so we populate the formulas for 10k rows.
Code below:
using DocumentFormat.OpenXml;
using DocumentFormat.OpenXml.Packaging;
using DocumentFormat.OpenXml.Spreadsheet;
using Microsoft.IT.Sales.RelationshipManagement.Segmentation.DataContracts;
using Newtonsoft.Json.Linq;
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Threading.Tasks;
namespace ConsoleApp1
{
class Program
{
static void Main(string[] args)
{
PopulateExcel("E:\\Formula.xlsx");
Console.WriteLine("Hello World!");
}
private static void PopulateExcel(string Path)
{
WorkbookPart WP;
//WorksheetPart WSP;
String rId;
Worksheet WS;
SheetData StD;
Row R1;
Row R2;
Row R3;
Cell C1;
Cell C2;
Cell C3;
CellFormula CF;
CalculationChainPart CP;
CalculationChain CC;
CalculationCell CCell;
Workbook Workbook;
Sheet ss;
Sheet Sheet;
using (SpreadsheetDocument spreadSheet = SpreadsheetDocument.Open(Path, true))
{
// Get the SharedStringTablePart. If it does not exist, create a new one.
WP = spreadSheet.WorkbookPart;
var wsp = spreadSheet.WorkbookPart.WorksheetParts.FirstOrDefault(); //.ElementAt(sheetnumber);
SheetData sheetData = wsp.Worksheet.Descendants<SheetData>().LastOrDefault();
R1 = GetRow(sheetData, 2);
C1 = new Cell();
SetCell(C1, "A1", 1);
sheetData.Append(R1);
R1.Append(C1);
C2 = new Cell();
SetCell(C2, "B1", 2);
R1.Append(C2);
spreadSheet.WorkbookPart.Workbook.CalculationProperties.ForceFullCalculation = true;
spreadSheet.WorkbookPart.Workbook.CalculationProperties.FullCalculationOnLoad = true;
wsp.Worksheet.Save();
// Close the document.
spreadSheet.Close();
}
}
private static Row GetRow(SheetData wsData, UInt32 rowIndex)
{
var row = wsData.Elements<Row>().
Where(r => r.RowIndex.Value == rowIndex).FirstOrDefault();
if (row == null)
{
row = new Row();
row.RowIndex = rowIndex;
wsData.Append(row);
}
return row;
}
private static void SetCell(Cell cell, string Reference, int Value)
{
cell.CellReference = Reference;
cell.DataType = CellValues.Number;
cell.CellValue = new CellValue();
cell.CellValue.Text = Value.ToString();
}
}
}
Please help me with the code.
I have a recursive method like this:
protected void executeAction( TreeItem ti )
{
boolean isChecked = ti.getChecked();
if ( isChecked )
{
Somedata data = (SomeData) ti.getData();
String action = data.getSelectedAction();
ActionManager am = data.getActionManager();
AbstractActionAgent agent = am.getAction( action );
if ( agent != null )
{
agent.updateModel( data ); //Makes a server trips and long computation
}
}
int itemcnt = ti.getItemCount();
TreeItem[] childTrees = ti.getItems();
for ( int i = 0; i < itemcnt; i++ )
{
executeAction( childTrees[i] );
}
}
My updateModel method freezes the UI, so I tried using Job, but my problem is that I want the update model to be executed for checked TreeItem only and it should follow the sequence of checked TreeItems. If I use Job, I have no control over which checked TreeIem is processed first. Also I tried putting the whole executeAction method in a Job, but ran into invalid thread while accessing the TreeItem.
I need some ideas so that I can spwan a new thread while maintaining the sequence and not freezing my UI.
Thanks.
You could try this. Collect you model objects in a Tree and run that updateModel in a separate job. The below code doesn't run. You may need to tweak it a bit.
class Node {
private SomeData nodeData;
private List<Node> children = new ArrayList();
// Create getters, setters..
}
protected void executeAction( TreeItem ti, Node parentNode ) {
boolean isChecked = ti.getChecked();
Node n = null;
if ( isChecked )
{
Somedata data = (SomeData) ti.getData();
if (parentNode != null) {
n = new Node();
n.setNodeData(data);
parentNode.addChild(n);
}
}
int itemcnt = ti.getItemCount();
TreeItem[] childTrees = ti.getItems();
for ( int i = 0; i < itemcnt; i++ )
{
executeAction( childTrees[i],n );
}
}
I have a cell table with an async data provider. If I update the data via the data provider the table renders the new data correctly but the selection model still holds onto and returns old objects.
Any ideas how to refresh the selection model?
I think you should make your SelectionModel work with different instance of the same "logical" object using the appropriate ProvidesKey. For instance, you could use ProvidesKey that calls getId on the object, so that two objects with the same such ID would be considered equal; so even if the SelectionModel holds onto the old object, it can still answer "yes, it's selected" when you give it the new object.
FYI, this is exactly what the EntityProxyKeyProvider does (using the stableId of the proxy). And the SimpleKeyProvider, used by default when you don't specify one, uses the object itself as its key.
I came across the same issue. Currently I have this as single selection model.
SelectedRow = store it when you select it.
Then when data is reloaded you can clear it by
celltable.getSelectionModel().setSelected(SelectedRow, false);
I guess it is too late for you but hope it helps someone else.
Here is my manual method for refreshing the SelectionModel. This allows you to use the selectedSet() when needed and it will actually contain the current data, rather than the old data - including the removal of deleted rows and updated fields!
I have included bits & pieces of a class extending DataGrid. This should have all the logic at least to solve your problems.
When a row is selected, call saveSelectionKeys().
When the grid data is altered call refeshSelectedSet().
If you know the key type, you can replace the isSameKey() method with something easier to deal with. This class uses generics, so this method attempts to figure out the object conversion itself.
.
public abstract class AsyncDataGrid<T> extends DataGrid<T> {
...
private MultiSelectionModel<T> selectionModel_;
private ListDataProvider<T> dataProvider_;
private List<T> dataList_;
private Set<Object> priorSelectionKeySet_;
private boolean canCompareKeys_;
...
public AsyncDataGrid( final ProvidesKey<T> keyProvider ){
super( keyProvider );
...
dataProvider_ = new ListDataProvider<T>();
dataList_ = dataProvider_.getList();
canCompareKeys_ = true;
...
}
private void saveSelectionKeys(){
priorSelectionKeySet_ = new HashSet<Object>();
Set<T> selectedSet = selectionModel_.getSelectedSet();
for( Iterator<T> it = selectedSet.iterator(); it.hasNext(); ) {
priorSelectionKeySet_.add( super.getValueKey( it.next() ) );
}
}
private void refeshSelectedSet(){
selectionModel_.clear();
if( priorSelectionKeySet_ != null ){
if( !canCompareKeys_ ) return;
for( Iterator<Object> keyIt = priorSelectionKeySet_.iterator(); keyIt.hasNext(); ) {
Object priorKey = keyIt.next();
for( Iterator<T> it = dataList_.iterator(); it.hasNext(); ) {
T row = it.next();
Object rowKey = super.getValueKey( row );
if( isSameKey( rowKey, priorKey ) ) selectionModel_.setSelected( row, true );
}
}
}
}
private boolean isSameRowKey( final T row1, final T row2 ) {
if( (row1 == null) || (row2 == null) ) return false;
Object key1 = super.getValueKey( row1 );
Object key2 = super.getValueKey( row2 );
return isSameKey( key1, key2 );
}
private boolean isSameKey( final Object key1, final Object key2 ){
if( (key1 == null) || (key1 == null) ) return false;
if( key1 instanceof Integer ){
return ( ((Integer) key1) - ((Integer) key2) == 0 );
}
else if( key1 instanceof Long ){
return ( ((Long) key1) - ((Long) key2) == 0 );
}
else if( key1 instanceof String ){
return ( ((String) key1).equals( ((String) key2) ) );
}
canCompareKeys_ = false;
return false;
}
}
I fixed my particular issue by using the following code to return the visible selection. It uses the selection model to determine what is selected and combines this with what is visible. The objects themselves are returned from the CellTable data which is always upto date if the data has ever been changed via an async provider (the selection model data maybe stale but the keys will be correct)
public Set<T> getVisibleSelection() {
/*
* 1) the selection model contains selection that can span multiple pages -
* we want to return just the visible selection
* 2) return the object from the cellTable and NOT the selection - the
* selection may have old, stale, objects if the data has been updated
* since the selection was made
*/
Set<Object> selectedSet = getKeys(selectionModel.getSelectedSet());
List<T> visibleSet = cellTable.getVisibleItems();
Set<T> visibleSelectionSet = new HashSet<T>();
for (T visible : visibleSet) {
if (selectedSet.contains(KEY_PROVIDER.getKey(visible))) {
visibleSelectionSet.add(visible);
}
}
return visibleSelectionSet;
}
public static Set<Object> getKeys(Collection<T> objects) {
Set<Object> ids = new HashSet<Object>();
for (T object : objects) {
ids.add(KEY_PROVIDER.getKey(object));
}
return ids;
}
I am using GWT 2.3.I which I am using GWT cell table.
Here below is the code for my cell table:
public class FormGrid extends SuperGrid {
List<Form> formList;
#Override
public void setColumns(CellTable table) {
TextColumn<Form> nameColumn = new TextColumn<Form>() {
#Override
public String getValue(Form object) {
return object.getName();
}
};
table.addColumn(nameColumn, "Name");
}
#Override
public void setData() {
if (formList != null && formList.size() > 0) {
AsyncDataProvider<Form> provider = new AsyncDataProvider<Form>() {
#Override
protected void onRangeChanged(HasData<Form> display) {
int start = display.getVisibleRange().getStart();
int end = start + display.getVisibleRange().getLength();
end = end >= formList.size() ? formList.size() : end;
List<Form> sub = formList.subList(start, end);
updateRowData(start, sub);
}
};
provider.addDataDisplay(getTable());
provider.updateRowCount(formList.size(), true);
}
}
public List<Form> getFormList() {
return formList;
}
public void setFormList(List<Form> formList) {
this.formList = formList;
}
}
In this my set column and set data will be called fro super class flow.This cell table is working fine.
Now I want to put a filter type facility (like search) in this cell table.It should be like, there is a texbox above the cell table and what ever written in that text box, it should fire a like query to all form name for that text box value.
for example I have 1000 form in the grid.Now if user writes 'app' in some filter textbox above the cell table the all the form which have 'app' in there name will be filtered and grid has only those forms only.
This is the first case:
Another case is I am only render one column in grid name.I have two more properties in form (description,tag).But I am not rendering them.now for filter if user writes 'app' in filter box then it should make a query to all three (name, description, and tag) and should return if 'app' matched to any of three.
I am not getting how to apply filter in cell table.
Please help me out.Thanks in advance.
You can find an implementation in the expenses sample.
Here is a short summary of the steps
1.) Create a Textbox and a SearchButton.
2.) add a clickHandler to the SearchButton (You can also add KeyUpHandler to the Textbox alternatively)
searchButton.addClickHandler(new ClickHandler() {
public void onClick(ClickEvent event) {
search();
}
});
3.) In the search function retrieve the searchString and store it.
private void search() {
searchString = searchBox.getText();
setData();
}
4.) modify your setdata() function to take searchString into account
#Override
public void setData() {
if (formList != null && formList.size() > 0) {
AsyncDataProvider<Form> provider = new AsyncDataProvider<Form>() {
#Override
protected void onRangeChanged(HasData<Form> display) {
int start = display.getVisibleRange().getStart();
int end = start + display.getVisibleRange().getLength();
//new function if searchString is specified take into account
List<Form> sub = getSubList(start,end);
end = end >= sub.size() ? sub.size() : end;
updateRowData(sub.subList(start, end);, sub);
}
};
provider.addDataDisplay(getTable());
provider.updateRowCount(formList.size(), true);
}
}
private List<Form> getSubList(int start, int end) {
List<Form> filtered_list = null;
if (searchString != null) {
filtered_list= new ArrayList<Form>();
for (Form form : formList) {
if (form.getName().equals(searchString) || form.getTag().equals(searchString) || form.getDescription().equals(searchString))
filtered_list.add(form);
}
}
else
filtered_list = formList;
return filtered_list;
}
can propose another solution what can be used quite easy multiple times.
Idea is to create custom provider for your celltable.
GWT celltable filtering
Video in this post shows it in action.
Here is the part of code of custom list data provider which u have to implement.
#Override
protected void updateRowData(HasData display, int start, List values) {
if (!hasFilter() || filter == null) { // we don't need to filter, so call base class
super.updateRowData(display, start, values);
} else {
int end = start + values.size();
Range range = display.getVisibleRange();
int curStart = range.getStart();
int curLength = range.getLength();
int curEnd = curStart + curLength;
if (start == curStart || (curStart < end && curEnd > start)) {
int realStart = curStart < start ? start : curStart;
int realEnd = curEnd > end ? end : curEnd;
int realLength = realEnd - realStart;
List<t> resulted = new ArrayList<t>(realLength);
for (int i = realStart - start; i < realStart - start + realLength; i++) {
if (filter.isValid((T) values.get(i), getFilter())) {
resulted.add((T) values.get(i));
}
}
display.setRowData(realStart, resulted);
display.setRowCount(resulted.size());
}
}
}
Like several other people, I'm having problems serializing Entity Framework objects, so that I can send the data over AJAX in a JSON format.
I've got the following server-side method, which I'm attempting to call using AJAX through jQuery
[WebMethod]
public static IEnumerable<Message> GetAllMessages(int officerId)
{
SIBSv2Entities db = new SIBSv2Entities();
return (from m in db.MessageRecipients
where m.OfficerId == officerId
select m.Message).AsEnumerable<Message>();
}
Calling this via AJAX results in this error:
A circular reference was detected while serializing an object of type \u0027System.Data.Metadata.Edm.AssociationType
Which is because of the way the Entity Framework creates circular references to keep all the objects related and accessible server side.
I came across the following code from (http://hellowebapps.com/2010-09-26/producing-json-from-entity-framework-4-0-generated-classes/) which claims to get around this problem by capping the maximum depth for references. I've added the code below, because I had to tweak it slightly to get it work (All angled brackets are missing from the code on the website)
using System.Web.Script.Serialization;
using System.Collections.Generic;
using System.Collections;
using System.Linq;
using System;
public class EFObjectConverter : JavaScriptConverter
{
private int _currentDepth = 1;
private readonly int _maxDepth = 2;
private readonly List<int> _processedObjects = new List<int>();
private readonly Type[] _builtInTypes = new[]{
typeof(bool),
typeof(byte),
typeof(sbyte),
typeof(char),
typeof(decimal),
typeof(double),
typeof(float),
typeof(int),
typeof(uint),
typeof(long),
typeof(ulong),
typeof(short),
typeof(ushort),
typeof(string),
typeof(DateTime),
typeof(Guid)
};
public EFObjectConverter( int maxDepth = 2,
EFObjectConverter parent = null)
{
_maxDepth = maxDepth;
if (parent != null)
{
_currentDepth += parent._currentDepth;
}
}
public override object Deserialize( IDictionary<string,object> dictionary, Type type, JavaScriptSerializer serializer)
{
return null;
}
public override IDictionary<string,object> Serialize(object obj, JavaScriptSerializer serializer)
{
_processedObjects.Add(obj.GetHashCode());
Type type = obj.GetType();
var properties = from p in type.GetProperties()
where p.CanWrite &&
p.CanWrite &&
_builtInTypes.Contains(p.PropertyType)
select p;
var result = properties.ToDictionary(
property => property.Name,
property => (Object)(property.GetValue(obj, null)
== null
? ""
: property.GetValue(obj, null).ToString().Trim())
);
if (_maxDepth >= _currentDepth)
{
var complexProperties = from p in type.GetProperties()
where p.CanWrite &&
p.CanRead &&
!_builtInTypes.Contains(p.PropertyType) &&
!_processedObjects.Contains(p.GetValue(obj, null)
== null
? 0
: p.GetValue(obj, null).GetHashCode())
select p;
foreach (var property in complexProperties)
{
var js = new JavaScriptSerializer();
js.RegisterConverters(new List<JavaScriptConverter> { new EFObjectConverter(_maxDepth - _currentDepth, this) });
result.Add(property.Name, js.Serialize(property.GetValue(obj, null)));
}
}
return result;
}
public override IEnumerable<System.Type> SupportedTypes
{
get
{
return GetType().Assembly.GetTypes();
}
}
}
However even when using that code, in the following way:
var js = new System.Web.Script.Serialization.JavaScriptSerializer();
js.RegisterConverters(new List<System.Web.Script.Serialization.JavaScriptConverter> { new EFObjectConverter(2) });
return js.Serialize(messages);
I'm still seeing the A circular reference was detected... exception being thrown!
I solved these issues with the following classes:
public class EFJavaScriptSerializer : JavaScriptSerializer
{
public EFJavaScriptSerializer()
{
RegisterConverters(new List<JavaScriptConverter>{new EFJavaScriptConverter()});
}
}
and
public class EFJavaScriptConverter : JavaScriptConverter
{
private int _currentDepth = 1;
private readonly int _maxDepth = 1;
private readonly List<object> _processedObjects = new List<object>();
private readonly Type[] _builtInTypes = new[]
{
typeof(int?),
typeof(double?),
typeof(bool?),
typeof(bool),
typeof(byte),
typeof(sbyte),
typeof(char),
typeof(decimal),
typeof(double),
typeof(float),
typeof(int),
typeof(uint),
typeof(long),
typeof(ulong),
typeof(short),
typeof(ushort),
typeof(string),
typeof(DateTime),
typeof(DateTime?),
typeof(Guid)
};
public EFJavaScriptConverter() : this(1, null) { }
public EFJavaScriptConverter(int maxDepth = 1, EFJavaScriptConverter parent = null)
{
_maxDepth = maxDepth;
if (parent != null)
{
_currentDepth += parent._currentDepth;
}
}
public override object Deserialize(IDictionary<string, object> dictionary, Type type, JavaScriptSerializer serializer)
{
return null;
}
public override IDictionary<string, object> Serialize(object obj, JavaScriptSerializer serializer)
{
_processedObjects.Add(obj.GetHashCode());
var type = obj.GetType();
var properties = from p in type.GetProperties()
where p.CanRead && p.GetIndexParameters().Count() == 0 &&
_builtInTypes.Contains(p.PropertyType)
select p;
var result = properties.ToDictionary(
p => p.Name,
p => (Object)TryGetStringValue(p, obj));
if (_maxDepth >= _currentDepth)
{
var complexProperties = from p in type.GetProperties()
where p.CanRead &&
p.GetIndexParameters().Count() == 0 &&
!_builtInTypes.Contains(p.PropertyType) &&
p.Name != "RelationshipManager" &&
!AllreadyAdded(p, obj)
select p;
foreach (var property in complexProperties)
{
var complexValue = TryGetValue(property, obj);
if(complexValue != null)
{
var js = new EFJavaScriptConverter(_maxDepth - _currentDepth, this);
result.Add(property.Name, js.Serialize(complexValue, new EFJavaScriptSerializer()));
}
}
}
return result;
}
private bool AllreadyAdded(PropertyInfo p, object obj)
{
var val = TryGetValue(p, obj);
return _processedObjects.Contains(val == null ? 0 : val.GetHashCode());
}
private static object TryGetValue(PropertyInfo p, object obj)
{
var parameters = p.GetIndexParameters();
if (parameters.Length == 0)
{
return p.GetValue(obj, null);
}
else
{
//cant serialize these
return null;
}
}
private static object TryGetStringValue(PropertyInfo p, object obj)
{
if (p.GetIndexParameters().Length == 0)
{
var val = p.GetValue(obj, null);
return val;
}
else
{
return string.Empty;
}
}
public override IEnumerable<Type> SupportedTypes
{
get
{
var types = new List<Type>();
//ef types
types.AddRange(Assembly.GetAssembly(typeof(DbContext)).GetTypes());
//model types
types.AddRange(Assembly.GetAssembly(typeof(BaseViewModel)).GetTypes());
return types;
}
}
}
You can now safely make a call like new EFJavaScriptSerializer().Serialize(obj)
Update : since version Telerik v1.3+ you can now override the GridActionAttribute.CreateActionResult method and hence you can easily integrate this Serializer into specific controller methods by applying your custom [GridAction] attribute:
[Grid]
public ActionResult _GetOrders(int id)
{
return new GridModel(Service.GetOrders(id));
}
and
public class GridAttribute : GridActionAttribute, IActionFilter
{
/// <summary>
/// Determines the depth that the serializer will traverse
/// </summary>
public int SerializationDepth { get; set; }
/// <summary>
/// Initializes a new instance of the <see cref="GridActionAttribute"/> class.
/// </summary>
public GridAttribute()
: base()
{
ActionParameterName = "command";
SerializationDepth = 1;
}
protected override ActionResult CreateActionResult(object model)
{
return new EFJsonResult
{
Data = model,
JsonRequestBehavior = JsonRequestBehavior.AllowGet,
MaxSerializationDepth = SerializationDepth
};
}
}
and finally..
public class EFJsonResult : JsonResult
{
const string JsonRequest_GetNotAllowed = "This request has been blocked because sensitive information could be disclosed to third party web sites when this is used in a GET request. To allow GET requests, set JsonRequestBehavior to AllowGet.";
public EFJsonResult()
{
MaxJsonLength = 1024000000;
RecursionLimit = 10;
MaxSerializationDepth = 1;
}
public int MaxJsonLength { get; set; }
public int RecursionLimit { get; set; }
public int MaxSerializationDepth { get; set; }
public override void ExecuteResult(ControllerContext context)
{
if (context == null)
{
throw new ArgumentNullException("context");
}
if (JsonRequestBehavior == JsonRequestBehavior.DenyGet &&
String.Equals(context.HttpContext.Request.HttpMethod, "GET", StringComparison.OrdinalIgnoreCase))
{
throw new InvalidOperationException(JsonRequest_GetNotAllowed);
}
var response = context.HttpContext.Response;
if (!String.IsNullOrEmpty(ContentType))
{
response.ContentType = ContentType;
}
else
{
response.ContentType = "application/json";
}
if (ContentEncoding != null)
{
response.ContentEncoding = ContentEncoding;
}
if (Data != null)
{
var serializer = new JavaScriptSerializer
{
MaxJsonLength = MaxJsonLength,
RecursionLimit = RecursionLimit
};
serializer.RegisterConverters(new List<JavaScriptConverter> { new EFJsonConverter(MaxSerializationDepth) });
response.Write(serializer.Serialize(Data));
}
}
You can also detach the object from the context and it will remove the navigation properties so that it can be serialized. For my data repository classes that are used with Json i use something like this.
public DataModel.Page GetPage(Guid idPage, bool detach = false)
{
var results = from p in DataContext.Pages
where p.idPage == idPage
select p;
if (results.Count() == 0)
return null;
else
{
var result = results.First();
if (detach)
DataContext.Detach(result);
return result;
}
}
By default the returned object will have all of the complex/navigation properties, but by setting detach = true it will remove those properties and return the base object only. For a list of objects the implementation looks like this
public List<DataModel.Page> GetPageList(Guid idSite, bool detach = false)
{
var results = from p in DataContext.Pages
where p.idSite == idSite
select p;
if (results.Count() > 0)
{
if (detach)
{
List<DataModel.Page> retValue = new List<DataModel.Page>();
foreach (var result in results)
{
DataContext.Detach(result);
retValue.Add(result);
}
return retValue;
}
else
return results.ToList();
}
else
return new List<DataModel.Page>();
}
I have just successfully tested this code.
It may be that in your case your Message object is in a different assembly? The overriden Property SupportedTypes is returning everything ONLY in its own Assembly so when serialize is called the JavaScriptSerializer defaults to the standard JavaScriptConverter.
You should be able to verify this debugging.
Your error occured due to some "Reference" classes generated by EF for some entities with 1:1 relations and that the JavaScriptSerializer failed to serialize.
I've used a workaround by adding a new condition :
!p.Name.EndsWith("Reference")
The code to get the complex properties looks like this :
var complexProperties = from p in type.GetProperties()
where p.CanWrite &&
p.CanRead &&
!p.Name.EndsWith("Reference") &&
!_builtInTypes.Contains(p.PropertyType) &&
!_processedObjects.Contains(p.GetValue(obj, null)
== null
? 0
: p.GetValue(obj, null).GetHashCode())
select p;
Hope this help you.
I had a similar problem with pushing my view via Ajax to UI components.
I also found and tried to use that code sample you provided. Some problems I had with that code:
SupportedTypes wasn't grabbing the types I needed, so the converter wasn't being called
If the maximum depth is hit, the serialization would be truncated
It threw out any other converters I had on the existing serializer by creating its own new JavaScriptSerializer
Here are the fixes I implemented for those issues:
Reusing the same serializer
I simply reused the existing serializer that is passed into Serialize to solve this problem. This broke the depth hack though.
Truncating on already-visited, rather than on depth
Instead of truncating on depth, I created a HashSet<object> of already seen instances (with a custom IEqualityComparer that checked reference equality). I simply didn't recurse if I found an instance I'd already seen. This is the same detection mechanism built into the JavaScriptSerializer itself, so worked quite well.
The only problem with this solution is that the serialization output isn't very deterministic. The order of truncation is strongly dependent on the order that reflections finds the properties. You could solve this (with a perf hit) by sorting before recursing.
SupportedTypes needed the right types
My JavaScriptConverter couldn't live in the same assembly as my model. If you plan to reuse this converter code, you'll probably run into the same problem.
To solve this I had to pre-traverse the object tree, keeping a HashSet<Type> of already seen types (to avoid my own infinite recursion), and pass that to the JavaScriptConverter before registering it.
Looking back on my solution, I would now use code generation templates to create a list of the entity types. This would be much more foolproof (it uses simple iteration), and have much better perf since it would produce a list at compile time. I'd still pass this to the converter so it could be reused between models.
My final solution
I threw out that code and tried again :)
I simply wrote code to project onto new types ("ViewModel" types - in your case, it would be service contract types) before doing my serialization. The intention of my code was made more explicit, it allowed me to serialize just the data I wanted, and it didn't have the potential of slipping in queries on accident (e.g. serializing my whole DB).
My types were fairly simple, and I didn't need most of them for my view. I might look into AutoMapper to do some of this projection in the future.