IOS: copy a file in documents folder

In my project I have two file .txt (in Resources folder), how can I copy them inside documents folder?

Copies txtFile from resource to document if not already present.

NSFileManager *fileManager = [NSFileManager defaultManager];
NSError *error;
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];

NSString *txtPath = [documentsDirectory stringByAppendingPathComponent:@"txtFile.txt"];

if ([fileManager fileExistsAtPath:txtPath] == NO) {
    NSString *resourcePath = [[NSBundle mainBundle] pathForResource:@"txtFile" ofType:@"txt"];
    [fileManager copyItemAtPath:resourcePath toPath:txtPath error:&error];
}

If you want to overwrite every time then try this:

if ([fileManager fileExistsAtPath:txtPath] == YES) {
    [fileManager removeItemAtPath:txtPath error:&error];
}

NSString *resourcePath = [[NSBundle mainBundle] pathForResource:@"txtFile" ofType:@"txt"];
[fileManager copyItemAtPath:resourcePath toPath:txtPath error:&error];

Swift 3

code for file is exist or not, if not then copy.

func CheckFileisExistOrNot(strPath:String) {
    let filemgr = FileManager.default
    if !filemgr.fileExists(atPath: strPath) {
        let resorcePath = Bundle.main.path(forResource: "\(Global.g_databaseName)", ofType: ".db")
        do {
            try filemgr.copyItem(atPath: resorcePath!, toPath: strPath)
        }catch{
            print("Error for file write")
        }
    }
}

NSFileManager *fileManager = [NSFileManager defaultManager];
NSError *error;
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [[paths objectAtIndex:0]stringByAppendingString:@"csvfile"];

NSString *txtPath = [documentsDirectory stringByAppendingPathComponent:@"sample.csv"];

if ([fileManager fileExistsAtPath:txtPath] == NO) {
    NSString *resourcePath = [[NSBundle mainBundle] pathForResource:@"sample" ofType:@".csv"];
    [fileManager copyItemAtPath:resourcePath toPath:txtPath error:&error];