如何通过iOS正则表达式判断纯数字及匹配11位手机号码？

//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]; 
  } 
 } 
 }