UITextField限制输入两位小数

(BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string{
// 限制只能输入数字
BOOL isHaveDian = YES;
if ([string isEqualToString:@" "]) {
return NO;
}

if ([textField.text rangeOfString:@"."].location == NSNotFound) {
isHaveDian = NO;
}
if ([string length] > 0) {

  unichar single = [string characterAtIndex:0];//当前输入的字符
  if ((single >= '0' && single <= '9') || single == '.') {//数据格式正确
      
      if([textField.text length] == 0){
          if(single == '.') {
              
              [textField.text stringByReplacingCharactersInRange:range withString:@""];
              return NO;
          }
      }
      
      //输入的字符是否是小数点
      if (single == '.') {
          if(!isHaveDian)//text中还没有小数点
          {
              isHaveDian = YES;
              return YES;
              
          }else{
              
              [textField.text stringByReplacingCharactersInRange:range withString:@""];
              return NO;
          }
      }else{
          if (isHaveDian) {//存在小数点
              
              //判断小数点的位数
              NSRange ran = [textField.text rangeOfString:@"."];
              if (range.location - ran.location <= 2) {
                  return YES;
              }else{
                  
                  return NO;
              }
          }else{
              return YES;
          }
      }
  }else{//输入的数据格式不正确
      
      [textField.text stringByReplacingCharactersInRange:range withString:@""];
      return NO;
  }

}
else
{
return YES;
}
}