self.subBtn.userInteractionEnabled = NO;设置点击无响应
self.subBtn.alpha = 0.4;//背景置灰色
//如果网址中存在中文,进行URLEncode.
//// NSString *newUrlStr = [urlStr stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
//UITextFile
http://blog.csdn.net/u011334685/article/details/46470579