5 回答

• 1

  试试这个：

  const validate = data =>  /^\w+\s*\w+ ?$/.test(data) && data.length <= 50
  
  const testData = ['this works', 'this    too ', '  this fails', 'firstname lastname ', ' firstname middlename lastname ']
  
  for (let temp of testData) {
      console.log(`${temp} ${validate(temp)}`)
  }
  

  回复于 2024-04-29T09:21:01+08:00
• 0

  这是一个正则表达式，涵盖了您的所有要求，包括长度检查：

  ^(?!.{51,})(\w+\s+\w+ ?)$
  

  Explanation:

  ^(?!.{51,})    assert that the string is not followed by 51 or more characters
  (
      \w+        match a word
      \s+        followed by one or more spaces
      \w+        followed by a second word
       ?         ending with an optional space
  )$
  

  function tests(str){
    var regex = /^(?!.{51,})(\w+\s+\w+ ?)$/;
    if (regex.test(str)) {
        console.log("passes");
    }
    else {
        console.log("fails");
    }
  }
  tests("firstname lastname ");  // passes
  tests("first name last name"); // fails
  tests("123456789 1234567890123456789012345678901234567890"); // passes (length 50)
  tests("123456789 12345678901234567890123456789012345678901"); // fails (length 51)
  

  正则表达式101

  回复于 2024-04-29T09:21:01+08:00
• 1

  function tests(str){
    var pat=/^[a-zA-Z]+\s[a-zA-Z]+\s?$/;
    if(pat.test(str) && str.length<=50){
      console.log("true");
    }
    else{
      console.log("false");
    }
  }
  tests("firstname lastname "); //true
  tests("first name last name"); //flase
  

  回复于 2024-04-29T09:21:01+08:00
• 0

  您可以通过将字符串拆分为数组来检查字数

  var array = "some string".split(" "); //result - ["some","string"]
  

  现在你可以检查字数了

  var count = array.length; //will return 2
  

  你可以算上这样的字母

  var letterCount = "some string".length; //will return 11
  

  比使用正则表达式更简单，更好 .

  回复于 2024-04-29T09:21:01+08:00
• 0

  这种模式有助于 /^[a-Z]+\s[a-Z]+\s?$/

  <input type="text" pattern="^[a-Z]+\s[a-Z]+\s?$" title="Must be two words...">
  

  回复于 2024-04-29T09:21:01+08:00