utf8与gbk互转

1.gbk转utf8

    

    NSData *uncompressedData = [request responseData];

    NSStringEncoding enc = CFStringConvertEncodingToNSStringEncoding(kCFStringEncodingGB_18030_2000);

    NSString* jsonString = [[NSString alloc]initWithData:uncompressedData encoding:enc];

    NSLog(@"jsonString = %@", jsonString);

2,utf8转gbk

  1)  NSStringEncoding enc = CFStringConvertEncodingToNSStringEncoding(kCFStringEncodingGB_18030_2000); 

     str = [str stringByAddingPercentEscapesUsingEncoding:enc];

  2)  urlString = (NSString *)CFBridgingRelease(CFURLCreateStringByAddingPercentEscapes(kCFAllocatorDefault, (CFStringRef)urlString, nil, nil, enc));