javascript - 如何使用 javascript 验证文本字符串？

Question

所以我想创建一个提示，要求输入客户名称。我想确保它的格式是这样的:“姓氏、名字、中间名首字母”并且名称不超过 20 个字符。到目前为止，这是我所拥有的，但不确定从这里去哪里。

<script language="JavaScript">
//Get the name
var name = prompt("What is your Name?");

//validate
if(name)
//output
document.write ("That is your name! :)");

else
document.write ("Please use the format Last name, first name, middle initial");
 </script>

Answer 1

看看下面使用正则表达式的简单步骤:

// Get name
var name = prompt("What is your Name?");

// match name with regular expression
if (name.match("^[A-Za-z]{1,20}, [A-Za-z]{1,20}, [A-Za-z]{1,20}")) {
    document.write("That is your name! :)");
} else {
    document.write("Please use the format Last name, first name, middle initial");
}

结果:

匹配:

1. abc, xyz, m ,
2. abcabcabc、xyzzyz、先生

不匹配:

1. , xyz, m,
2. 123, a, b,
3. iammorethantwentycharactersfirstname, middle, initial