js调整数字为价格的格式

例子：
比如输入123456会自动调整为123,456的格式。

<script language="javascript" type="text/javascript" >

			function isInputedNum (txtId) {
				if (!event.shiftKey) {
					if (!((event.keyCode >= 48 && event.keyCode <= 57) 
							|| event.keyCode == 8 
							|| event.keyCode == 9 
							|| event.keyCode == 46 
							|| (event.keyCode >= 96 && event.keyCode <= 105) 
							|| (event.keyCode >= 37 && event.keyCode <= 40))) {
								//alert(event.keyCode);
						event.returnValue = false;
						return false;
					}
					if (event.keyCode != 9) {
						if (txtId.value == "0") {
							txtId.value = "";
						}
					}
					return true;
				} else {
					event.returnValue = false;
					return false;
				}
			}
			
/**
 * remove comar from a number String 
 */			
function removeComarValue(txtId) {
	if(txtId.readOnly == true)
		return;
	var txt = removeComar(txtId.value);
	txtId.value = txt;
}

/**
 * remove comar from a number String 
 */			
function removeComar(txtNum) {
	var numStr = txtNum;
	var indx = numStr.indexOf(",");
	if (indx != -1) {
		numStr = numStr.replace(",", "");
		numStr = removeComar(numStr);
	}
	return numStr;
}


/**
 * add comar to a number String 
 */
function resetComarValue(txtId) {
	if(txtId.readOnly == true) return;
	var value = txtId.value.replace(/^0+/g, '');
	if (value == '') value = '0';
	var txt = resetComar(value);
	txtId.value = txt;
}

/**
 * add comar to a number String 
 */			
function resetComar(txtNum) {
	txtNum = removeComar(txtNum);
	if (txtNum.length <= 3) {
		return txtNum;
	}
	var threeOnes = new Array(0);
	var last = txtNum.length;
	var first = last - 3;
	var arrayIndx = 0;
	while (first >= 0) {
		var txtNumStr = txtNum.substring(first, last);
		threeOnes[arrayIndx] = txtNum.substring(first, last);
		arrayIndx++;
		last = first;
		first = last - 3;
		if (first < 0 && last > 0) {
			first = 0;
		}
	}
	var txtNumCopy = "";
	for (var i = threeOnes.length - 1; i >= 0; i--) {
		if (txtNumCopy == "") {
			txtNumCopy = threeOnes[i];
		} else {
			txtNumCopy = txtNumCopy + "," + threeOnes[i];
		}
	}

	if(txtNumCopy.charAt(0) == '-') {
		if(txtNumCopy.charAt(1) == ',') {
			txtNumCopy = "-" + txtNumCopy.substring(2);
		}
	}

	return txtNumCopy;
}
</script>


<input type="text" id="price" name="price" maxlength="11" onkeydown="return isInputedNum(this)" onfocus="removeComarValue(this)" onblur="resetComarValue(this)" style="text-align: right;" />