//是否是纯数字 
+ (BOOL)isNumText:(NSString *)str{ 
 NSString * regex  = @"(/^[0-9]*$/)"; 
 NSPredicate * pred  = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", regex]; 
 BOOL isMatch   = [pred evaluateWithObject:str]; 
 if (isMatch) { 
  return YES; 
 }else{ 
  return NO; 
 } 
}

- (NSString *) trimming { 
 return [self stringByTrimmingCharactersInSet: [NSCharacterSet whitespaceCharacterSet]]; 
} 
//判断是不是纯数字 
 [NSCharacterSet decimalDigitCharacterSet]; 
 if ([[textField.text stringByTrimmingCharactersInSet: [NSCharacterSet decimalDigitCharacterSet]]trimming].length >0) { 
  DLog(@"不是纯数字"); 
 }else{ 
  DLog(@"纯数字！"); 
 } 

//正则表达式匹配11位手机号码 
 NSString *regex = @"^((13[0-9])|(15[^4,\\D])|(18[0,0-9]))\\d{8}$"; 
 NSPredicate *pred = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", regex]; 
 BOOL isMatch = [pred evaluateWithObject:_telField.text]; 
if(isMatch) { //有效手机号 
}else//无效手机号 
 { 
   if (ios7) { 
    UIAlertView *alertView = [[UIAlertView alloc]initWithTitle:nil message:@"无效的手机号码,请重新输入..." delegate:self cancelButtonTitle:nil otherButtonTitles:@"确定", nil nil]; 
    alertView.tag = 104; 
    [alertView show]; 
   }else 
   { 
    UIAlertController*alertController = [UIAlertController alertControllerWithTitle:nil message:@"无效的手机号码,请重新输入..." preferredStyle:UIAlertControllerStyleAlert]; 
    UIAlertAction *otherAction = [UIAlertAction actionWithTitle:@"确定" style:UIAlertActionStyleDefault handler:^(UIAlertAction*action) { 
     [_telField selectAll:self]; 
    }]; 
    [alertController addAction:otherAction]; 
    [self presentViewController:alertController animated:YES completion:nil]; 
   } 
  } 
 }