javaScript检查字符串中至少一个字母数字字符

Question

In my application someone can submit text from another language. I'd like for only English alphanumeric strings to be entered. I've got this JavaScript function working but wondering if this is the best method for doing this?

var string = $('input[name=title]').val();
if((/\d/.test(string) || /[a-zA-Z]/.test(string)) === false) {
    alert('Field has no Alphanumeric characters.');
    fPass = false;
}

Even if some just enters 1 character I want that to be allowed, as long as it is a number or a character from one of the 26 letters in the English alphabet (case insensitive)

Without using a function here is what I've come up with

if((/[\da-z]/i.test(string)) === false) {
    alert('Please use alphanumeric characters.')
}

Answer 1

You can combine your regex into one expression.

function hasAlphanumeric(str) {
  return /\d|[A-z]/.test(str)
}

Answer 2

You can use

^[\da-z]+$

---

 let allowAlphanumeric = (str) =>{ return /^[\\da-z]+$/i.test(str) } console.log(allowAlphanumeric('$#@')) console.log(allowAlphanumeric('')) console.log(allowAlphanumeric(' ')) console.log(allowAlphanumeric('abchbchdb12e44'))