js操作cookie实现记住密码

使用js操作cookie实现记住密码功能

原文出处：http://www.w3schools.com/js/js_cookies.asp

js代码：

<script type="text/javascript">

    function getCookie(c_name) {
        var c_value = document.cookie;
        var c_start = c_value.indexOf(" " + c_name + "=");
        if (c_start == -1) {
            c_start = c_value.indexOf(c_name + "=");
        }
        if (c_start == -1) {
            c_value = null;
        }
        else {
            c_start = c_value.indexOf("=", c_start) + 1;
            var c_end = c_value.indexOf(";", c_start);
            if (c_end == -1) {
                c_end = c_value.length;
            }
            c_value = unescape(c_value.substring(c_start, c_end));
        }
        return c_value;
    }

    function setCookie(c_name, value, exdays) {
        var exdate = new Date();
        exdate.setDate(exdate.getDate() + exdays);
        var c_value = escape(value) + ((exdays == null) ? "" : "; expires=" + exdate.toUTCString());
        document.cookie = c_name + "=" + c_value;
    }

    function Deletecookie(c_name, value, exdays) {
        var exdate = new Date();
        exdate.setDate(exdate.getDate() - 1);
        var cval = getCookie(c_name);
        var c_value = escape(value) + ((exdays == null) ? "" : "; expires=" + exdate.toUTCString());
        document.cookie = c_name + "=" + c_value;
    }


    function form_submit() {
        var username = document.getElementById("txtName").value;
        var password = document.getElementById("txtPwd").value;
        if (document.getElementById("ckrmbpw").checked) {
            setCookie("username", username, 7);
            setCookie("password", password, 7);
        }
        else {
            Deletecookie("password", password, 0);
        }
    }

    window.onload = function () {
        if (document.cookie != "") {
            var username = getCookie('username');
            var pwd = getCookie('password');
            if (pwd == null || pwd == "") {
                document.getElementById("ckrmbpw").checked = false;
                pwd = "";
            }
            else {

                document.getElementById("ckrmbpw").checked = true;
            }
            document.getElementById("txtName").value = username;
            document.getElementById("txtPwd").value = pwd;
        }
    }

</script>

Html代码

 <table width="100%" border="0" cellpadding="0" cellspacing="0" id="formtab">
        <tr>
            <td>
                用户名:<input name="txtName" type="text" id="txtName" style="width: 80px;" />
            </td>
            <td>
                密码:<input name="txtPwd" type="password" id="txtPwd" style="width: 80px;" />
            </td>
            <td>
                <input type="checkbox" id="ckrmbpw" />记住密码
                <input type="button" name="btnSub" value="登录" id="btnSub" onclick="form_submit()" />
            </td>
        </tr>
    </table>

实现效果：