带空格的银行账户显示输入

//-----------银行账户，4个数字用空格隔开----------- 
//-----------显示字段 class = bankNumFm;
//-----------值字段class = bankNum
DSDetail.bindBankNumFormat = function(bankEl){
    if(!bankEl.size()){
        return ;
    }
    var formatBankNum = function(value){
        if(value){
            value = value.replace(/(\d{4}\s*)/g,function($0,$1){
                return $1.replace(/\s+$/g,"") + ' ';
            });
            //消灭最后的空格
            value = value.replace(/\s+$/,"");
        }
        return value;
    }; 

    var setValue = function(fmEl,valEl,value){

        value = value.replace(/[^\d]/g,"");
        //设置隐藏域
        valEl.val(value.replace(/\s+/g,""));
        //设置显示域
        fmEl.val(formatBankNum(value));
    };

    bankEl.each(function(){
        var fmEl = $(this);
        var valEl = fmEl.siblings(".bankNumVal");

	    if("onpropertychange" in this){
	        fmEl.bind("propertychange",function(){
	            setValue(fmEl,valEl,this.value);
	        });
	    }else if("oninput" in this){
	        fmEl.bind("input",function(e){
	            setValue(fmEl,valEl,this.value);
	        });
	    }
	    fmEl.bind("keydown",function(e){
	        if ((e.keyCode >= 48 && e.keyCode <= 57) ||   //
	            (e.keyCode >= 96 && e.keyCode <= 105) ||  //小键盘数字
	                e.which === 37 || e.which === 39      //左右键
	                 || e.which === 8 || e.which === 46){ //回退、删除键

	            setValue(fmEl,valEl,this.value);
	        }else{
	            return false;
	        }
	    });

	    //初始化
	    setValue(fmEl,valEl,fmEl.val());

    });
};

    //--------银行账户格式化---------------
    DSDetail.bindBankNumFormat($(".bankNumFm"));