ios 9.0之后的url 中文格式化

#pragma mark - url 中文格式化
+ (NSString *)strUTF8Encoding:(NSString *)str
{
    /*! ios9适配的话 打开第一个 */
    if ([[UIDevice currentDevice] systemVersion].floatValue >= 9.0)
    {        
        return [str stringByAddingPercentEncodingWithAllowedCharacters:[NSCharacterSet characterSetWithCharactersInString:@"`#%^{}\"[]|\\<> "].invertedSet];
    }
    else
    {
        return [str stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
    }
}