[Cocoa]iOS中的url編碼問題

iOS中的url編碼問題

羅朝輝 (http://www.cnblogs.com/kesalin/)

本文遵循“署名-非商業用途-保持一致”創作公用協議 

NSString 的 stringByAddingPercentEscapesUsingEncoding 可以對 url 參數進行編碼，但是有點小問題，不會對所有需要編碼的字元都編碼。我們可以通過  CFStringRef 的 

CFURLCreateStringByAddingPercentEscapes 函數來封裝這個功能。代碼如下：

- (NSString *)encodeToPercentEscapeString: (NSString *) input
{
// Encode all the reserved characters, per RFC 3986
// (<http://www.ietf.org/rfc/rfc3986.txt>)
    NSString *outputStr = (NSString *) 
    CFURLCreateStringByAddingPercentEscapes(kCFAllocatorDefault,
                                            (CFStringRef)input,
                                            NULL,
                                            (CFStringRef)@"!*'();:@&=+$,/?%#[]",
                                            kCFStringEncodingUTF8);
return outputStr;
}

- (NSString *)decodeFromPercentEscapeString: (NSString *) input
{
    NSMutableString *outputStr = [NSMutableString stringWithString:input];
    [outputStr replaceOccurrencesOfString:@"+"
                               withString:@" "
                                  options:NSLiteralSearch
                                    range:NSMakeRange(0, [outputStr length])];

return [outputStr stringByReplacingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
}

 

測試代碼：

    NSString * testUrl      = @"http://search.google.com?keywords=($# it's {a*123})00!*'();:@&=+$,/?%#[]";
    NSLog(@"original: %@", testUrl);

    NSString * encodeStr    = [self encodeToPercentEscapeString:testUrl];
    NSLog(@"encoded: %@", encodeStr);

    NSString * encodeStr2   = [testUrl stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
    NSLog(@"encoded2:%@", encodeStr2);

    NSString * decodeStr    = [self decodeFromPercentEscapeString:encodeStr];
    NSLog(@"decoded: %@", decodeStr);

 

結果如下：

>> original: http://search.google.com?keywords=($# it's {a*123})00!*'();:@&=+$,/?%#[]
>> encoded: http%3A%2F%2Fsearch.google.com%3Fkeywords%3D%28%24%23%20it%27s%20%7Ba%2A123%7D%2900%21%2A%27%28%29%3B%3A%40%26%3D%2B%24%2C%2F%3F%25%23%5B%5D
>> encoded2: http://search.google.com?keywords=($%23%20it's%20%7Ba*123%7D)00!*'();:@&=+$,/?%25%23%5B%5D
>> decoded: http://search.google.com?keywords=($# it's {a*123})00!*'();:@&=+$,/?%#[]