//IOS最简单的url编码
NSString *stringEncode = [stringEncode stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
//IOS对特殊字符的处理
stringEncode = (NSString *)CFBridgingRelease(CFURLCreateStringByAddingPercentEscapes(kCFAllocatorDefault,(CFStringRef) stringEncode, NULL, CFSTR(":/?#[]@!$&’()*+,;="), kCFStringEncodingUTF8));