iOS将控制台Log日志转为输出为文本文件

- (void)redirectNSlogToDocumentFolder

{

NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);

NSString *documentDirectory = [paths objectAtIndex:0];

NSString *fileName = [NSString stringWithFormat:@"MrNSLog.txt"];// 注意不是NSData!

NSString *logFilePath = [documentDirectory stringByAppendingPathComponent:fileName];

// 先删除已经存在的文件

NSFileManager *defaultManager = [NSFileManager defaultManager];

[defaultManager removeItemAtPath:logFilePath error:nil];

// 将log输入到文件

freopen([logFilePath cStringUsingEncoding:NSASCIIStringEncoding], "a+", stdout);

freopen([logFilePath cStringUsingEncoding:NSASCIIStringEncoding], "a+", stderr);

}

2.在didFinishLaunchingWithOptions中调用 :
[self redirectNSlogToDocumentFolder];