Write a file on iOS - ios

Question

How do I write a file on iOS? I'm trying to do it with the following code but I'm doing something wrong:
char *saves = "abcd";
NSData *data = [[NSData alloc] initWithBytes:saves length:4];
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
NSString *appFile = [documentsDirectory stringByAppendingPathComponent:#"MyFile"];
[data writeToFile:appFile atomically:YES];
I have created MyFile.txt on resources.

Answer 1

May be this is useful to you.
//Method writes a string to a text file
-(void) writeToTextFile{
//get the documents directory:
NSArray *paths = NSSearchPathForDirectoriesInDomains
(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
//make a file name to write the data to using the documents directory:
NSString *fileName = [NSString stringWithFormat:#"%#/textfile.txt",
documentsDirectory];
//create content - four lines of text
NSString *content = #"One\nTwo\nThree\nFour\nFive";
//save content to the documents directory
[content writeToFile:fileName
atomically:NO
encoding:NSUTF8StringEncoding
error:nil];
}
//Method retrieves content from documents directory and
//displays it in an alert
-(void) displayContent{
//get the documents directory:
NSArray *paths = NSSearchPathForDirectoriesInDomains
(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
//make a file name to write the data to using the documents directory:
NSString *fileName = [NSString stringWithFormat:#"%#/textfile.txt",
documentsDirectory];
NSString *content = [[NSString alloc] initWithContentsOfFile:fileName
usedEncoding:nil
error:nil];
//use simple alert from my library (see previous post for details)
[ASFunctions alert:content];
[content release];
}

Answer 2

Your code is working at my end, i have just tested it. Where are you checking your changes? Use Documents directory path. To get path -
NSLog(#"%#",documentsDirectory);
and copy path from console and then open finder and press Cmd+shift+g and paste path here and then open your file

Answer 3

Swift
func saveFile() {
let paths = NSSearchPathForDirectoriesInDomains(.DocumentDirectory, .UserDomainMask, true)
let documentsDirectory = paths[0] as! String
let fileName = "\(documentsDirectory)/textFile.txt"
let content = "Hello World"
content.writeToFile(fileName, atomically: false, encoding: NSUTF8StringEncoding, error: nil)
}
func loadFile() {
let paths = NSSearchPathForDirectoriesInDomains(.DocumentDirectory, .UserDomainMask, true)
let documentsDirectory = paths[0] as! String
let fileName = "\(documentsDirectory)/textFile.txt"
let content: String = String(contentsOfFile: fileName, encoding: NSUTF8StringEncoding, error: nil)!
println(content)
}
Swift 2
func saveFile() {
let paths = NSSearchPathForDirectoriesInDomains(.DocumentDirectory, .UserDomainMask, true)
let documentsDirectory = paths[0]
let fileName = "\(documentsDirectory)/textFile.txt"
let content = "Hello World"
do{
try content.writeToFile(fileName, atomically: false, encoding: NSUTF8StringEncoding)
}catch _ {
}
}
func loadFile()->String {
let paths = NSSearchPathForDirectoriesInDomains(.DocumentDirectory, .UserDomainMask, true)
let documentsDirectory = paths[0]
let fileName = "\(documentsDirectory)/textFile.txt"
let content: String
do{
content = try String(contentsOfFile: fileName, encoding: NSUTF8StringEncoding)
}catch _{
content=""
}
return content;
}
Swift 3
func saveFile() {
let paths = NSSearchPathForDirectoriesInDomains(.documentDirectory, .userDomainMask, true)
let documentsDirectory = paths[0]
let fileName = "\(documentsDirectory)/textFile.txt"
let content = "Hello World"
do{
try content.write(toFile: fileName, atomically: false, encoding: String.Encoding.utf8)
}catch _ {
}
}
func loadFile()->String {
let paths = NSSearchPathForDirectoriesInDomains(.documentDirectory, .userDomainMask, true)
let documentsDirectory = paths[0]
let fileName = "\(documentsDirectory)/textFile.txt"
let content: String
do{
content = try String(contentsOfFile: fileName, encoding: String.Encoding.utf8)
} catch _{
content=""
}
return content;
}

Answer 4

Try making
NSString *appFile = [documentsDirectory stringByAppendingPathComponent:#"MyFile"];
as
NSString *appFile = [documentsDirectory stringByAppendingPathComponent:#"MyFile.txt"];