은행 카드 번호의 4자리마다 자동으로 공백을 삽입하는 jquery 기반 구현 코드

$(function() {
 
      $('#kahao').on('keyup', function(e) {
       //只对输入数字时进行处理
        if((e.which >= 48 && e.which <= 57) ||
            (e.which >= 96 && e.which <= 105 )){
          //获取当前光标的位置
          var caret = this.selectionStart
          //获取当前的value
          var value = this.value
          //从左边沿到坐标之间的空格数
          var sp = (value.slice(0, caret).match(/\s/g) || []).length
          //去掉所有空格
          var nospace = value.replace(/\s/g, &#39;&#39;)
          //重新插入空格
          var curVal = this.value = nospace.replace(/(\d{4})/g, "$1 ").trim()
          //从左边沿到原坐标之间的空格数
          var curSp = (curVal.slice(0, caret).match(/\s/g) || []).length
         //修正光标位置
         this.selectionEnd = this.selectionStart = caret + curSp - sp
         
        }
      })
    })

 

  
  
  


 

  
  <script>
    $(function() {
 
      $(&amp;#39;#kahao&amp;#39;).on(&amp;#39;keyup&amp;#39;, function(e) {
       //只对输入数字时进行处理
        if((e.which &gt;= 48 &amp;&amp; e.which &lt;= 57) ||
            (e.which &gt;= 96 &amp;&amp; e.which &lt;= 105 )){
          //获取当前光标的位置
          var caret = this.selectionStart
          //获取当前的value
          var value = this.value
          //从左边沿到坐标之间的空格数
          var sp = (value.slice(0, caret).match(/\s/g) || []).length
          //去掉所有空格
          var nospace = value.replace(/\s/g, &amp;#39;&amp;#39;)
          //重新插入空格
          var curVal = this.value = nospace.replace(/(\d{4})/g, &quot;$1 &quot;).trim()
          //从左边沿到原坐标之间的空格数
          var curSp = (curVal.slice(0, caret).match(/\s/g) || []).length
         //修正光标位置
         this.selectionEnd = this.selectionStart = caret + curSp - sp
         
        }
      })
    })
  </script>