/*只能输入数字,两位小数*/
formatter(val){
val = val.replace(/[^\d.]/g,""); //清除“数字”和“.”以外的字符
val = val.replace(/\.{2,}/g,"."); //只保留第一个. 清除多余的
val = val.replace(".","$#$").replace(/\./g,"").replace("$#$",".");
val = val.replace(/^(\-)*(\d+)\.(\d\d).*$/,'$1$2.$3');//只能输入两个小数
return val
},