摘要：
varianputDom=document.getElementById（'inputDom'）；varmaxLen=0；inputDom.oninput=函数（）{varvalue=this.value；v
<html> <head> <title></title> </head> <body> <input id="inputDom" />
<script type="text/javascript"> var inputDom = document.getElementById('inputDom'); var maxLen = 0; inputDom.oninput = function() { var value = this.value; var valueLen = value.length; var foucsNum = getCursortPosition(inputDom); if(valueLen > 0){ var c = value.replace(/s/g, ""); var Len = c.length; var List = c.split(''); var initNum = 0; for(var i=1;i<Len;i++) { if(i%4 == 0) { //每四位分一组 List.splice(i+initNum,0,' '); //此处为使用空格分隔 initNum++ } } this.value = List.join(''); if(maxLen < this.value.length) { if(foucsNum%5 == 0) { setTimeout(function() { setCaretPosition(inputDom,foucsNum+1) },0); }else { setTimeout(function() { setCaretPosition(inputDom,foucsNum) },0); } }else { if(foucsNum%5 == 0) { setTimeout(function() { setCaretPosition(inputDom,foucsNum-1) },0); }else { setTimeout(function() { setCaretPosition(inputDom,foucsNum) },0); } } maxLen = this.value.length; } } //控制光标移动时，需要使用定时器，避免出现光标控制失效的情况 function getCursortPosition(ctrl) { //获取光标的位置 var CaretPos = 0; // IE Support if (document.selection) { ctrl.focus(); var Sel = document.selection.createRange(); Sel.moveStart ('character', -ctrl.value.length); CaretPos = Sel.text.length; } // Firefox support else if (ctrl.selectionStart || ctrl.selectionStart == '0') CaretPos = ctrl.selectionStart; return (CaretPos); } function setCaretPosition(ctrl, pos) { //设置光标的位置 if(ctrl.setSelectionRange){ ctrl.focus(); ctrl.setSelectionRange(pos,pos); } else if (ctrl.createTextRange) { var range = ctrl.createTextRange(); range.collapse(true); range.moveEnd('character', pos); range.moveStart('character', pos); range.select(); } } </script> </body> </html>
如果以上代码无法满足业务需要，可以使用插件Cleave.js，进行input框中数据的格式化；