jQuery限制文本框的輸入長度

jQuery限制文本框輸入，包含粘貼。

//限制文本框的輸入長度
$(function () {
    $(document).on("keypress", ".txt-valid-len", function (e) {
        if (e.keyCode == 8) {
            return true;
        }
        else {
            var len = $(this).data("maxlength") || 0;
            if (len > 0) {
                return (this.value.length <= len);
            }
        }
        return true;
    });
    //粘貼
    $(document).on("paste", ".txt-valid-len", function () {
        var len = $(this).data("maxlength") || 0;
        if (len > 0) {
            return ((this.value.length + event.clipboardData.getData('Text').length) <= len);
        }
        return true;
    });
    $(document).on("keyup input", ".txt-valid-len", function (e) {
        var keyCode = e.keyCode || e.which || e.charCode;
        if (keyCode == 46 || keyCode == 8) {

        }
        else {
            var len = $(this).data("maxlength") || 0;
            if (len > 0) {
                if (this.value.length > len) {
                    this.value = com.cutStr(this.value, len, "");
                }
            }
        }
    });
});

 里面有用到：http://www.cnblogs.com/wz122889488/p/6273018.html里面的方法