价格输入框的校验（数字，两个小数）

 

　　　　　　　　<td ><input type="text" name="price" value="${storeProdute.retail_price }" id="price" size="5" style="text-align: right;"  
             οnkeyup="checkNum(this)"></td>
             <!-- οnkeyup="if(isNaN(value))execCommand('undo')" onafterpaste="if(isNaN(value))execCommand('undo')" -->

 

    function checkNum(obj){

        obj.value = obj.value.replace(/[^\d.]/g,"");
        
        obj.value = obj.value.replace(/^\./g,"");
        
        obj.value = obj.value.replace(/\.{2,}/g,".");
        
        obj.value = obj.value.replace(".","$#$").replace(/\./g,"").replace("$#$",".");
        
        obj.value = obj.value.replace(/^(\-)*(\d+)\.(\d\d).*$/,'$1$2.$3');
        
    }