关于IOS判断字符串长度的方法

 

     NSString *text=@"helloworld你好吗";//16    NSUInteger length= text.length;    NSUInteger length2=[text lengthOfBytesUsingEncoding:NSUTF8StringEncoding];    NSLog(@"length=%lu,length2=%lu,length3=%lu",(unsigned long)length ,(unsigned long)length2,[self unicodeLengthOfString:text]);

-(NSUInteger) unicodeLengthOfString: (NSString *) text {    NSUInteger asciiLength = 0;    for (NSUInteger i = 0; i < text.length; i++) {        unichar uc = [text characterAtIndex: i];        asciiLength += isascii(uc) ? 1 : 2;    }    NSUInteger unicodeLength = asciiLength / 2;    if(asciiLength % 2) {        unicodeLength++;    }    return asciiLength;}