js 获取字符串的字节数

function getLength(str) {
    var totalLength = 0;
    var charCode;
    for (var i = 0; i < str.length; i++) {
        charCode = str.charCodeAt(i);
        if (charCode < 0x007f)  {
            totalLength++;
        } else if ((0x0080 <= charCode) && (charCode <= 0x07ff))  {
            totalLength += 2;
        } else if ((0x0800 <= charCode) && (charCode <= 0xffff))  {
            totalLength += 3;
        } else{
            totalLength += 4;
        }
    }
    return totalLength;
}

var oneName = “sodasjd”;
alert(oneName);