<!DOCTYPE html>
<html>
  <head>
    <meta charset="utf-8">
    <title></title>
    <script type="text/javascript">
      // 找出字符串中“how are you doing？”中所有小于字母“s”的字符，并在页面输出
      window.onload = function(){
        var txt = "how are you doing？";
        var ts = "s";
        // console.log(txt.length);
        for(var i = 0; i <= txt.length; i++){
          var t = txt.charAt(i);
          console.log(t);
          if(ts > t){
            document.write(t+'、');
          }
        }

      }
    </script>
  </head>
  <body>
  </body>
</html>

js实现字符串比较_字符串比较