How to get the "real length" of a NSString

Say I got a st开发者_高级运维ring like:

NSString *str = @"abc一二三";

which contains both English and Chinese, if I use the [str length] I got the result 6. The result I want is 1+1+1+2+2+2 = 9, one Chinese character equals 2 English letter.

Hope somebody could help me, thanks^_^

Well, it would be tedious, but you could create your own String Length method. A method with a switch statement that examines the characters individually and assigns integer values accordingly, then returns the total. For example:

- (NSInteger)specialStringLength:(NSString *)theString {
     int realLength=0;
     for(int x=0;x<[theString length];x++)
     {
          char thisOne = [theString characterAtIndex:x];
          switch(thisOne) {
               case 'a':
                    realLength++;
                    break;
               // and so on...
               case '三':
                    realLength+=2;
                    break;
               // and so on...
          }
     }
     return realLength;
}

Maybe you can convert NSString to NSData, and use the length of NSData.