Objective－C，UrlEncode，UrlDecode

UrlDecode对字符串进行Url解码，即解析UrlEncode编码后的字符串

UrlEncode的编码规则为：

1.数字字母保持不变

2.空格变为‘＋’

3.其他字符被编码成‘％’＋它们GB2312或UTF－8编码，

如“测试”，GB2312:%B2%E2%CA%D4；UTF－8:%E6%B5%8B%E8%AF%95

实现代码： 

NSString *chinese = @"测试";

NSString *encodeStr = [chinese stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];

NSLog(@"%@", encodeStr);　　//输出：%E6%B5%8B%E8%AF%95

 

UrlDecode实现代码

NSString *result = [encodeStr stringByReplacingOccurrencesOfString:@"+" withString:@" "];

result = [result stringByReplacingPercentEscapesUsingEncoding:NSUTF8StringEncoding];

NSLog(@"%@",result);　　//输出：测试