网站 二级域名验证

A.aspx

<script src="js/Check.js" type="text/javascript"></script>

<asp:TextBox ID="txtSubDomain" runat="server" onchange="CheckSubDomain()" MaxLength="20"></asp:TextBox>

<asp:Label ID="lblErrorSubDomain" runat="server" ForeColor="Red" Font-Size="Small"></asp:Label>

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Check.js

var xmlHttp = null;

function CheckSubDomain() {

    try {

        xmlHttp_SD = new ActiveXObject("Msxml2.XMLHTTP");

    }

    catch (err1) {

        try {

            xmlHttp_SD = new ActiveXObject("Microsoft.XMLHTTP");

        }

        catch (err2) {

            xmlHttp_SD = new XMLHttpRequest();

        }

    }

    var mUser = document.getElementById("txtSubDomain");

    var mWSTID = document.getElementById("inputWebsiteTypeID");

    if (mUser.value != "") {

        var url = document.getElementById('txtSubDomain').value;

        var regDomain = /^[a-zA-Z0-9][-a-zA-Z0-9]{0,62}$/;

        var isMatch = url.match(regDomain);

        if (isMatch) {

            var mUrl = "chkuser.aspx?SDID=" + mUser.value + "&WSTID=" + mWSTID.value;

            xmlHttp_SD.open("GET", mUrl, true);

            xmlHttp_SD.onreadystatechange = OnHandler_SD;

            xmlHttp_SD.send(null);

        }

        else {

            var exists = document.getElementById("lblErrorSubDomain");

            exists.innerHTML = "子域名不合法！";

        }

    }

    else {

        var exists = document.getElementById("lblErrorSubDomain");

        exists.innerHTML = "不可为空！";

    }

}

function OnHandler_SD() {

    if (xmlHttp_SD.readyState == 4) {

        var isValid = xmlHttp_SD.responseText;

        var exists = document.getElementById("lblErrorSubDomain");

        exists.innerHTML = isValid.substring(0, isValid.indexOf('<'));

    }

}