javascript indexof regex A-Za-z0-9 总是返回 false

Question

我创建了一个 JS fiddle https://jsfiddle.net/95r110s9/#&togetherjs=Emdw6ORNpc

HTML

<input id="landlordstreetaddress2" class="landlordinputs" onfocusout="validateinputentries()" />

JS

validateinputentries(){

landlordstreetaddress2 = document.getElementById('landlordstreetaddress2').value;

 goodcharacters = "/^[a-zA-Z0-9#.,;:'\s]+$/gi";

 for (var i = 0; i < landlordstreetaddress2.length; i++){

  if (goodcharacters.indexOf(landlordstreetaddress2.charAt(i)) != -1){

       console.log('Character is valid');

  }

 }

}

它从输入中提取值，并运行包含 A-Z a-z 和 0-9 以及一些附加字符的 indexOf 正则表达式。

问题是它适用于 BCDEFG...etc 和 12345...etc 的条目，但是当我输入“A”或“Z”或“0”或“1”时，它返回不正确。

我需要它返回与 0123456789、ABCDEF...XYZ 和 abcdef...xyz 相同的内容

我应该指出，以下内容确实按预期工作:

var badcharacters = "*|,\":<>[]`\';@?=+/\\";
badcharacter = false;

//firstname
for (var i = 0; i < landlordfirstname.value.length; i++){

   if (badcharacters.indexOf(landlordfirstname.value.charAt(i)) != -1){

        badcharacter = true;
        break;
   }

   if(landlordfirstname.value.charAt(0) == " "){

        badcharacter = true;
        break;
   }

}

Answer 1

String.prototype.indexOf()

The indexOf() method returns the index within the calling String object of the first occurrence of the specified value, starting the search at fromIndex. Returns -1 if the value is not found.

所以，您正在尝试搜索这个值"/^[a-zA-Z0-9#.,;:'\s]+$/gi"，而“永远”不会在输入的字符串中找到。

您实际上想根据输入的值测试该正则表达式。

/^[a-zA-Z0-9#.,;:'\s]+$/gi.test(landlordstreetaddress2)

function validateinputentries() {
  var landlordstreetaddress2 = document.getElementById('landlordstreetaddress2').value;

  if (/^[a-zA-Z0-9#.,;:'\s]+$/gi.test(landlordstreetaddress2)) {
    console.log('Characters are valid');
  } else {
    console.log('Characters are invalid');
  }
}

<input id="landlordstreetaddress2" class="landlordinputs" onfocusout="validateinputentries()" />