File from Documents into NSData - iphone

Question

i want to grab a file from the Documents Directory into a NSData Object, but if i do so my NSData is always NIL:
filepath = [[NSString alloc] init];
filepath = [self.GetDocumentDirectory stringByAppendingPathComponent:fileNameUpload];
NSData *data = [[NSFileManager defaultManager] contentsAtPath:filepath];
-(NSString *)GetDocumentDirectory{
fileMgr = [NSFileManager defaultManager];
homeDir = [NSHomeDirectory() stringByAppendingPathComponent:#"Documents"];
return homeDir;
}
at this point, i always get an exception that my data is NIL:
[request addRequestHeader:#"Md5Hash" value:[data MD5]];
i checked, there´s no File but i dunno why! I created that file before with:
NSMutableString *xml = [[NSMutableString alloc] initWithString:[xmlWriter toString]];
NSArray *paths = NSSearchPathForDirectoriesInDomains
(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
//make a file name to write the data to using the documents directory:
NSMutableString *fileName = [NSMutableString stringWithFormat:#"%#/7-speed-",
documentsDirectory];
[xml writeToFile:fileName
atomically:NO
encoding:NSStringEncodingConversionAllowLossy
error:nil];
Solved it by:
[xml writeToFile:fileName
atomically:YES
encoding:NSUTF8StringEncoding
error:nil];

Answer 1

check file exists:
if([[NSFileManager defaultManager] fileExistsAtPath:filepath)
{
NSData *data = [[NSFileManager defaultManager] contentsAtPath:filepath];
}
else
{
NSLog(#"File not exits");
}

Answer 2

Swift 3 Version
let filePath = fileURL.path
if FileManager.default.fileExists(atPath: filePath) {
if let fileData = FileManager.default.contents(atPath: filePath) {
// process the file data
} else {
print("Could not parse the file")
}
} else {
print("File not exists")
}