Question

我尝试运行此代码，但它不起作用，有人可以帮忙吗？

var lastName = document.queryselector('lastName');
var message = document.queryselector('message');

function checkFirstLetterOfLastName() {
 if (/^[A-L]/.test(lastName)) {
 message.textContent = 'Go stand in first line';
 } else {
 message.textContent = 'Go stand in first line';
 }
}

checkFirstLetterOfLastName();

Answer 1

以下是使用正则表达式的工作示例：

function checkFirstLetterOfLastName(lastName) {
  if (/^[A-L]/.test(lastName)) {
    console.log(lastName, 'starts with A-L');
  } else {
    console.log(lastName, 'does not start with A-L');
  }
}

checkFirstLetterOfLastName('Carlson');
checkFirstLetterOfLastName('Mathews');

Answer 2

＆＃13;

public ActionResult ThrowJsonError(Exception ex)
{
   Response.StatusCode = (int)System.Net.HttpStatusCode.BadRequest;
   Response.StatusDescription = ex.Message; // does not work
   Response.StatusDescription = ex.Message.Replace('\r', ' ').Replace('\n', ' '); // works

   return Json(new { Message = ex.Message }, JsonRequestBehavior.AllowGet);
}

＆＃13;

Answer 3

foo('Avery');
foo('David');
foo('Laura');
foo('Michael');
foo('Zachary');

function foo(x) {
  if(x.match(/^[A-L]/i)) {
    console.log('Go stand in first line.')
  }
  else console.log('Go stand in second line.');
}

这对你有用吗？

Answer 4

我会使用RegEx并使用expression.test方法，如下所示：

// a string that starts with a letter between A and L
var str = 'Hello!'
// a string that does not start with a letter between A and L
var notPass = 'SHould not pass'
// Note: this only checks for capital letters
var expr = /[A-L]/
console.log(expr.test(str[0]))
console.log(expr.test(notPass[0]))

如果要比较的语句，则lastName以字母A-L开头

4 个答案: