asked on

Referencing controls in an ASP.NET Repeater using JavaScript

I'm currently using the following code to populate a textbox with values from other text boxes

<html>
<head>
<script>
function populate_it(){
  var d = document;
  d.getElementById("tbResult").value = d.getElementById("tbEntry1").value+"-"+d.getElementById("tbEntry2").value;
}
</script>
</head>
<body>
tbEntry1: <input type="text" name="tbEntry1" id="tbEntry1" oninput="populate_it()"><br/>
tbEntry2: <input type="text" name="tbEntry2" id="tbEntry2" oninput="populate_it()"><br/>
tbResult: <input type="text" name="tbResult" id="tbResult">
</body>
</html>

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My textboxes are now all in a repeater nested in a GridView like so:

<asp:GridView ID="GridView1" runat="server" >
        <asp:Repeater ID="Repeater1" runat="server">
        <ItemTemplate>
tbEntry1: <input type="text" name="tbEntry1" id="tbEntry1" oninput="populate_it()"><br/>
tbEntry2: <input type="text" name="tbEntry2" id="tbEntry2" oninput="populate_it()"><br/>
tbResult: <input type="text" name="tbResult" id="tbResult">
 </ItemTemplate>
<asp:Repeater>
</asp:GridView>

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Obviously my script is no longer picking up. How do I change this so that I can find the controls in the repeater?

Ersoy Hasan

You wont be able to pick up the controls because Ids in the DOM must be unique. Better define a class in the inputs and select them by Document.getElementsByClassName() (https://developer.mozilla.org/en-US/docs/Web/API/document.getElementsByClassName) and give your inputs unique ids so you will know what you have selected.

ASKER CERTIFIED SOLUTION

Ersoy Hasan

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Member_2_1242703

ASKER

Second option doesnt work. In my repeater class on databound, I've added:

            Dim GI As TextBox = f.Item.FindControl("tbEntry1")
            Dim SN As TextBox = f.Item.FindControl("tbSEntry2")

            GI.Attributes.Add("oninput", "populate_it('" & GI.ClientID & "')")
            SN.Attributes.Add("oninput", "populate_it('" & SN.ClientID & "')")

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What would be the proper script method now?

Member_2_1242703

ASKER

nevermind, that wont work either, huh?

Ersoy Hasan

GI.Attributes.Add("class", "tbEntry1");
GI.Attributes.Add("oninput", "populate_it(this)")
SN.Attributes.Add("class", "tbEntry2");
SN.Attributes.Add("oninput", "populate_it(this)")

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and make the changes I showed you in the previous comment.

P.S.
You don't even have to do it in codebehind just change the html in the repeater. as I showed you.

Ersoy Hasan

here is a fiddle with the second option.
http://jsfiddle.net/qlayer/mjvuL26z/

Member_2_1242703

ASKER

HTML side:

<script type="text/javascript">
    window.populate_it = function populate_it(el) {
        //traverse up to the div
        var d = el.parentElement;
        // select childs 
        d.getElementsByClassName("tbResult")[0].value = d.getElementsByClassName("tbEntry1")[0].value + "-" + d.getElementsByClassName("tbEntry2")[0].value;
    }
</script>


        <asp:Repeater ID="Repeater1" runat="server" OnItemDataBound="OnRepeaterDataBound">
    <ItemTemplate>
    <div class="entry">
        <asp:TextBox ID="tbEntry1" runat="server" class="tbEntry1" name="tbEntry1" oninput="populate_it(this)"></asp:TextBox><br />
        <asp:TextBox ID="tbEntry2" runat="server" class="tbEntry2" name="tbEntry2" oninput="populate_it(this)"></asp:TextBox><br />
        <asp:TextBox ID="tbResult" runat="server" class="tbResult" name="tbResult"></asp:TextBox><br />
</div>
</ItemTemplate>
    </asp:Repeater>

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CodeBehind:

   Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
        If Not Page.IsPostBack Then
            BindData()
        End If
    End Sub
    Sub BindData()
        Dim ds As New Data.DataSet
        Dim da As New Data.SqlClient.SqlDataAdapter("SELECT * FROM tblWorkOrders WHERE ProjectID = '1'", connn)
        da.Fill(ds, "employees")
        Repeater1.DataSource = ds.Tables("employees")
        Repeater1.DataBind()
    End Sub
    Protected Sub OnRepeaterDataBound(s As Object, f As RepeaterItemEventArgs)
        If f.Item.ItemType = ListItemType.AlternatingItem Or f.Item.ItemType = ListItemType.Item Then
            Dim GI As TextBox = f.Item.FindControl("tbEntry1")
            Dim SN As TextBox = f.Item.FindControl("tbEntry2")

            GI.Attributes.Add("oninput", "populate_it('" & GI.ClientID & "')")
            SN.Attributes.Add("oninput", "populate_it('" & SN.ClientID & "')")
        End If
    End Sub

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When I ViewSource:

    <div class="entry">
        <input name="Repeater1$ctl00$tbEntry1" type="text" id="Repeater1_ctl00_tbEntry1" class="tbEntry1" name="tbEntry1" oninput="populate_it(&#39;Repeater1_ctl00_tbEntry1&#39;)" /><br />
        <input name="Repeater1$ctl00$tbEntry2" type="text" id="Repeater1_ctl00_tbEntry2" class="tbEntry2" name="tbEntry2" oninput="populate_it(&#39;Repeater1_ctl00_tbEntry2&#39;)" /><br />
        <input name="Repeater1$ctl00$tbResult" type="text" id="Repeater1_ctl00_tbResult" class="tbResult" name="tbResult" /><br />
</div>

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What am I doing wrong??

Ersoy Hasan

This has to be removed:

GI.Attributes.Add("oninput", "populate_it('" & GI.ClientID & "')")
SN.Attributes.Add("oninput", "populate_it('" & SN.ClientID & "')")

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or changed to this:

GI.Attributes.Add("oninput", "populate_it(this)")
SN.Attributes.Add("oninput", "populate_it(this)")

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Member_2_1242703

ASKER

I actually did like you said and just removed the code behind. Here's my code now:

HTML:

<head runat="server">
    <title></title>

<script type="text/javascript">
    window.populate_it = function populate_it(el) {
        //traverse up to the div
        var d = el.parentElement;
        // select childs 
        d.getElementsByClassName("tbResult")[0].value = d.getElementsByClassName("tbEntry1")[0].value + "-" + d.getElementsByClassName("tbEntry2")[0].value;
    }
</script>

</head>
<body>
    <form id="form1" runat="server">
  
        <asp:Repeater ID="Repeater1" runat="server">
    <ItemTemplate>
    <div class="entry">
        <asp:TextBox ID="tbEntry1" runat="server" class="tbEntry1" name="tbEntry1" oninput="populate_it(this)"></asp:TextBox><br />
        <asp:TextBox ID="tbEntry2" runat="server" class="tbEntry2" name="tbEntry2" oninput="populate_it(this)"></asp:TextBox><br />
        <asp:TextBox ID="tbResult" runat="server" class="tbResult" name="tbResult"></asp:TextBox><br />
</div>
</ItemTemplate>
    </asp:Repeater>
    </form>
</body>
</html>

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code behind:

    Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
        If Not Page.IsPostBack Then
            BindData()
        End If
    End Sub
    Sub BindData()
        Dim ds As New Data.DataSet
        Dim da As New Data.SqlClient.SqlDataAdapter("SELECT * FROM tblWorkOrders WHERE ProjectID = '1'", connn)
        da.Fill(ds, "employees")
        Repeater1.DataSource = ds.Tables("employees")
        Repeater1.DataBind()
    End Sub

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ViewSource:

    <div class="entry">
        <input name="Repeater1$ctl00$tbEntry1" type="text" id="Repeater1_ctl00_tbEntry1" class="tbEntry1" name="tbEntry1" oninput="populate_it(this)" /><br />
        <input name="Repeater1$ctl00$tbEntry2" type="text" id="Repeater1_ctl00_tbEntry2" class="tbEntry2" name="tbEntry2" oninput="populate_it(this)" /><br />
        <input name="Repeater1$ctl00$tbResult" type="text" id="Repeater1_ctl00_tbResult" class="tbResult" name="tbResult" /><br />
</div>

    <div class="entry">
        <input name="Repeater1$ctl01$tbEntry1" type="text" id="Repeater1_ctl01_tbEntry1" class="tbEntry1" name="tbEntry1" oninput="populate_it(this)" /><br />
        <input name="Repeater1$ctl01$tbEntry2" type="text" id="Repeater1_ctl01_tbEntry2" class="tbEntry2" name="tbEntry2" oninput="populate_it(this)" /><br />
        <input name="Repeater1$ctl01$tbResult" type="text" id="Repeater1_ctl01_tbResult" class="tbResult" name="tbResult" /><br />
</div>

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Still no luck

Ersoy Hasan

what browser are you trying this (because getElementsByClassName wont work on ie8) ?
I am trying your code in fiddle and it works. (see http://jsfiddle.net/qlayer/mjvuL26z/1/)

Member_2_1242703

ASKER

Awww man...that was it. IE8 is the default browser for my IDE. Just tried it in Chrome and it worked fine. Sorry about that! Thanks so much for sticking with me.

Member_2_1242703

ASKER

FYI..

This isn't working if I put the controls in a table inside the DIV unless they are all in the same TD
Question here:
https://www.experts-exchange.com/questions/28552285/JavaScript-GetElementsByClassName-inside-nested-table-or-nested-DIV-not-working.html

Member_2_1242703

ASKER

Have another one: http://www.experts-exchange.com/Programming/Languages/Scripting/JavaScript/Q_28555219.html