Javascript：输入验证

Question

我需要创建一个JS函数，允许用户使用这些req：

在输入字段中输入单词

• 单词10个字符的最大长度

• 字符串最大长度为30个字符

  onkeyup: return .split(' ').filter(
      function(what) {
          return /[\w\d]/.exec(what) != null && what.length <= 10 ? what : ''
      }
  ).join('').length > 0
  

Answer 1

是否有必要使用正则表达式？

function isValid(str, maxlength, maxWordLength)
{

  if ( !str || str.length > maxlength ) //if the string is not null and length greater than max length
  {
    return false;
  }
  var strArr = str.split(/(\s+)/); //okay a bit of regex here :) to split by white space
  return strArr.some( function(value){ return value.length > maxWordLength } ); //if any value inside this array has value greater than maxWordLength
}

console.log( isValid( "asdas as", 30, 10 ) );

您可以通过

在文本框的keyup事件上执行此操作

$( "#elementId" ).bind( "keyup", function(){ 

   isValid( $( this ).val(), 30, 10 );

} );

纯js

document.getElementById( "elementId" ).addEventListener ("keyup", function(){

   isValid( this.value, 30, 10 );

} );