CFURLCreateStringByAddingPercentEscapes

在 iOS 程序访问 HTTP 资源时需要对 URL 进行 Encode，比如像拼出来的 http://unmi.cc?p1=%+&sd f&p2=中文，其中的中文、特殊符号&％和空格都必须进行转译才能正确访问。现在以"?!@#$^&%*+,:;='\"`<>()[]{}/\\| "字符串为例子，用stringByAddingPercentEncodingWithAllowedCharacters取代CFURLCreateStringByAddingPercentEscapes

过期代码：

-(NSString *)urlEncode:(id)value
{
    return (NSString *)
    CFBridgingRelease(CFURLCreateStringByAddingPercentEscapes(kCFAllocatorDefault, (CFStringRef)[value description], NULL, (CFStringRef)@"#[]@!$'()*+,;\"<>%{}|^~`", kCFStringEncodingUTF8));
}

-(NSString *)URLDecodedString:(NSString *)str {
    NSString *decodedString=(__bridge_transfer NSString *)CFURLCreateStringByReplacingPercentEscapesUsingEncoding(NULL, (__bridge CFStringRef)str, CFSTR(""), CFStringConvertNSStringEncodingToEncoding(NSUTF8StringEncoding));
    
    return decodedString;
}

修改后：

static inline NSString * WebURLEncode(NSString * str)
{
    NSString *charactersToEscape = @"#[]@!$'()*+,;\"<>%{}|^~`";
    NSCharacterSet *allowedCharacters = [[NSCharacterSet characterSetWithCharactersInString:charactersToEscape] invertedSet];
   
    NSString *encodedUrl = [[str description] stringByAddingPercentEncodingWithAllowedCharacters:allowedCharacters];
    return encodedUrl;
}

static inline NSString *  WebURLDecodedString(NSString * str)
{
    return [str stringByRemovingPercentEncoding];
}