<div class="caigou"> <form action="" method="post"> <div class="num_box"> <a id="sub">-</a> <input id="num" class="num" name="num" value="1"> <a id="add">+</a> </div> </form> <div id="zong"> <b id="zongjia">{$xianjia}</b>元 </div> </div>
<script> var b_num=document.getElementById('num'); var b_sub=document.getElementById('sub'); var b_add=document.getElementById('add'); var b_zongjia=document.getElementById('zongjia'); var b_danjia=parseInt(b_zongjia.innerHTML); //只能是数字 b_num.onkeyup=function(){this.value=this.value.replace(/[^0-9]/g,''); jiesuan()} b_num.onafterpaste=function(){this.value=parseInt(this.value.replace(/[^0-9]/g,''));jiesuan()} //禁止选中 b_sub.onselectstart=function(){ return false;} b_add.onselectstart=function(){ return false;} //加减计算 b_sub.onclick=function(){ if(b_num.value<=1){ return false} b_num.value = parseInt(b_num.value)-1; jiesuan() } b_add.onclick=function(){ b_num.value = parseInt(b_num.value)+1; jiesuan() } function jiesuan(){ if(b_num.value==""){ b_num.value=0; b_zongjia.innerHTML=0; return} b_zongjia.innerHTML= parseInt(b_num.value)*b_danjia; } //禁止回车 b_num.onfocus=function(){ window.onkeydown=function(event){ if(event.keyCode==13||event.keyCode==109||event.keyCode==107){return false;} } } b_num.onblue=function(){ window.onkeydown=function(){}; } </script>