Hi
I am creating a simple calculation based application and at end i need to create a text file for the calculation made in that app.Now i want that whole result into the text file, i dont if we can create a text file through our application or not but need to create that and also if we are able to create it then can we transfer to our pc/mac .
If any tutorial is available it would be of great help .
Regards
Mrugen
Try:
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectoryPath = [paths objectAtIndex:0];
NSString *filePath = [documentsDirectoryPath stringByAppendingPathComponent:#"myfile.conf"];
NSString *settings = #"1.0,0.0,0.0,0,";
NSData* settingsData;
settingsData = [settings dataUsingEncoding: NSASCIIStringEncoding];
if ([settingsData writeToFile:filePath atomically:YES])
NSLog(#"writeok");
Taken from: http://sio2interactive.forumotion.net/t347-how-to-write-a-text-file-to-iphone#1847
Related
i am doing one iphone app, for that i have to store bulk of MP3 song and images.
can ay one tell me what is the best to store those in terms of performance.
Store the image and songs in the application directory. This is best and easy way to handle. Try the following code. it will be help you.
//Store Image/Songs files to Application Directory
+(BOOL)writeToFile:(NSData *)data fileName:(NSString *)fileName {
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
// the path to write file
NSString *appFile = [documentsDirectory stringByAppendingPathComponent:fileName];
return [data writeToFile:appFile atomically:YES];
}
//Image/songs - Retrieve from Application Directory
+(NSData *)readFromFile:(NSString *)fileName {
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
NSString *filePath = [documentsDirectory stringByAppendingPathComponent:fileName];
NSData *myData = [NSData dataWithContentsOfFile:filePath];
if (myData) {
return myData;
}
return nil;
}
store the MP3 song and images into resources folder of your app project and give the refrences in the sqlite database(because saving large files in sqlite database is not a good practice)
I would suggest you to store all items of large size on the device disk, i.e, Documents directory and store their physical path in core data or sqlite or at least in a plist file so that you can retrieve them as per your convenience.
i am using following code to log into a file...
NSData *dataToWrite = [[NSString stringWithString:#"log data"] dataUsingEncoding:NSUTF8StringEncoding];
NSString *docsDirectory = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) objectAtIndex:0];
NSString *path = [docsDirectory stringByAppendingPathComponent:#"fileName.txt"];
[dataToWrite writeToFile:path atomically:YES];
But when this method gets called again...it doest show the last entry...??
Could anyone suggest?
thanks
It is better you try using NSFileHandle , because the write operation to a file on NSData simply a convenience function and can not do a full fledged file operations like appending.
I had a look around, trying to find a straightforward method for first saving a MutableArray (which will contain different text arrays from UITextViews with returns etc.) into a txt-file and then loading the txt-file back into my MutableArray.
I didn't manage to come up with the reverse method (loading the text-file) and was wondering how I should go about this. I'm sure txt files and mutable arrays are not really compatible, especially if I want the MutableArray to hold various text strings from UITextViews.
Is there a way to mark the beginning of one section in a mutable array and the beginning of the next in a txt file? The aim would be to be able to edit the txt file both in the program and in a simple text editor without messing up the structure of the mutable array.
Can I use a certain special character (not \n obviously) in my text file so as to separate different objects?
Here is what I've come up with so far. Sorry, I'm a beginner and it's very basic. The first problem is that I get the error message 'NSMutableArray' may not respond to '-writeToFile:atomically:encoding:error:'. Next, I have no idea how to load the txt back into my Array. Finally, I'd like to come up with a way to separate the arrays in the txt so that it remains editable, but that would be the absolute icing. Perhaps a solution would be to save each Object in an Array in a separate txt file and then load each txt into the array?
// GENERATE ARRAY
NoteBook = [[NSMutableArray alloc] init];
for (int temp = 0; temp < 3; temp++) {
[NoteBook insertObject:#"Title\n\n Line1\nLine2..." atIndex:temp];
}
// SAVING MY MUTABLE ARRAY
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0]; // Get documents directory
NSError *error;
BOOL succeed = [NoteBook writeToFile:[documentsDirectory stringByAppendingPathComponent:#"myfile.txt"]
atomically:YES encoding:NSUTF8StringEncoding error:&error];
if (!succeed){
// Handle error here
}
// LOADING TEXTFILE AND PUT IT INTO A MUTABLE ARRAY
// NO IDEA... how to do this
Convert your arrays into strings, and vice versa, using, e.g.,
NSString* arrayText = [NoteBook componentsJoinedByString: #"<your-favourite-separator-string>"];
the write to file using [arrayText writeToFile...]
After reading a string back from a file, use
Notebook = [arrayText componentsSeparatedByString: #"<your-favourite-separator-string>"];
Lastly, don't do this. Save your array directly to a property list (read up on those) or JSON or some other structured data format.
Why not just turn the mutable array into JSON and write that string to a file? The inverse is to read the string from file and turn back into an array using the JSON parser. json-framework is very easy to use.
A benefit would be that you could create or modify your array by editing text files as long as you write valid JSON.
make NSMutableArray to NSArray .because NSMutableArray does not have writeToFile .
retriev array from file
NSArray *theCatalogInfo=nil;
NSString *theCatalogFilePath = [NSString stringWithFormat:#"%#/Documents/",NSHomeDirectory()];
theCatalogFilePath = [theCatalogFilePath stringByAppendingString:kCatalogCachePath];
if(nil!=theCatalogFilePath)
{
theCatalogInfo=[[NSArray alloc]initWithContentsOfFile:theCatalogFilePath];
}
Save array To file
NSString *theCatalogFilePath = [NSString stringWithFormat:#"%#/Documents/",NSHomeDirectory()];
theCatalogFilePath = [theCatalogFilePath stringByAppendingString:kCatalogCachePath];
[**YourArray** writeToFile:theCatalogFilePath atomically:YES];
Have a look at following three methods to create a text file, write to it and read the data from it.
The key is to store the different objects separated by space. And you should get it very simple.
-(void)createFile
{
NSArray *paths = NSSearchPathForDirectoriesInDomains
(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
NSString *filePath = [documentsDirectory stringByAppendingPathComponent:#"Sample.txt"];
NSFileManager * file_manager = [NSFileManager defaultManager];
if(![file_manager fileExistsAtPath:filePath])
{
[file_manager createFileAtPath:filePath contents:nil attributes:nil];
NSString *content = #"NULL NULL NULL";
[content writeToFile:filePath
atomically:NO
encoding:NSStringEncodingConversionAllowLossy
error:nil];
}
}
-(void)writeToFile
{
NSArray *paths = NSSearchPathForDirectoriesInDomains
(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
NSString *filePath = [documentsDirectory stringByAppendingPathComponent:#"Sample.txt"];
NSString *content = [NSString stringWithFormat:#"%# %# %#", obj1, obj2, obj3];
[content writeToFile:filePath
atomically:NO
encoding:NSStringEncodingConversionAllowLossy
error:nil];
}
-(void)readFromFile
{
objects = [[NSArray alloc] init];
NSArray *paths = NSSearchPathForDirectoriesInDomains
(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
NSString *filePath = [documentsDirectory stringByAppendingPathComponent:#"Sample.txt"];
if (filePath) {
NSString *myText = [NSString stringWithContentsOfFile:filePath encoding:NSASCIIStringEncoding error:nil];
if (myText) {
objects = [myText componentsSeparatedByString:#" "];
}
}
}
if your nsarray contains nsdictionary, nsarray, nsstring, nsnumber, nsdata or nsdate objects (no custom objects, int's, etc) you can simply write the contents of your mutable array to a plist file.
this will maintain the data structure you have and you can simply read that data right into an array. How I do it in a couple of my data classes is
NSArray *tempArray = [NSArray arrayWithContentsOfFile:[Utils getFileLocation]];
if (tempArray == nil) {
yourArray = [[NSMutableArray alloc] init];
} else {
yourArray = [[NSArray deepMutableCopy:tempArray] retain];
}
i can access .txt file from documents folder but how to access a folder content lets say documents/A
inside A i have ->a.html, update.cfg
now why i cant access update.cfg??
i am getting null value for zipPath
i tried this but no luck
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *aDirectory = [[paths objectAtIndex:0] stringByAppendingPathComponent:#"A"];
NSString *zipPath = [[NSBundle mainBundle] pathForResource:#"update" ofType:#"cfg" inDirectory:aDirectory];
still zipPath=NULL??
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *aDirectory = [[paths objectAtIndex:0] stringByAppendingPathComponent:#"A"];
My approach to get to the documentsfolder is a little bit different. (I hope you mean the Documents folder which every application has, not one created by yourself in the mainbundle.^^) I do it like this:
NSString *directoryPath = [[NSHomeDirectory() stringByAppendingPathComponent: #"Documents"] stringByAppendingPathComponent: #"A"];
This is the path to your directory called A in the documents folder. If you know the filename, than you can use another "stringByAppendingPathComponent". ;-) I hope it helps. Else ask again. :-D
after messing up i found this way to acces the file from folder
i got it
NSString *fileName = [NSString stringWithFormat:#"%#/update.cfg",
aDirectory];
NSString *content = [[NSString alloc] initWithContentsOfFile:fileName
usedEncoding:nil
error:nil];
thanks
i want to replace my sqlite DB stores on iphone by a sqlite which is on my server for an update.
how could i do that? i can download it and get it with an NSData object but how do i store it on the iphone and then replace the old one ?
thanks
That's pretty simple. It should just be something like this:
NSData *fetchedData = ...; /* downloaded using NSURLConnection or whatever*/
NSString *documentsPath = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) lastObject];
NSString *filePath = [documentsPath stringByAppendingPathComponent:#"DBName.sqlite"];
[fetchedData writeToFile:filePath atomically:YES];