ios - 如何将这个 objective-c 转换为 swift

Question

NSURL *url = [NSURL URLWithString:@"http://iminichrispy.com/Xcode/TextFromWeb.txt"];
    NSString *content = [NSString stringWithContentsOfURL:url encoding:NSStringEncodingConversionAllowLossy error:nil];
    label.text = content;

我尝试过以下方法

var url:NSURL = NSURL(string: "http://iminichrispy.com/Xcode/TextFromWeb.txt")

var content:NSString = NSString(contentsOfURL: url, encoding: NSStringEncodingDetectionAllowLossyKey, error: nil)

label.text = content

为零时，我不断收到错误:“调用中存在额外参数‘错误’”

Answer 1

encoding 参数应该是编码(它是一个整数)，而不是转换选项(它是一个字符串，因此类型不匹配):

var url:NSURL? = NSURL(string: "http://iminichrispy.com/Xcode/TextFromWeb.txt")

var content:NSString? = NSString(contentsOfURL: url!,
                                 encoding: NSUTF8StringEncoding,
                                 error: nil)