Getting index of a gridview when hyperlinkfield is clicked

Question

I have a web app(ASP.NET 2.0 using C#) that I am working on. In it, I have a gridview with a hyperlinkfield on a page(My_Page.aspx). When the Hyperlinkfield is clicked, it shows details on the same page.

<asp:HyperLinkField DataNavigateUrlFields="ID" 
                    DataNavigateUrlFormatString="My_Page.aspx?id={0}"
                    DataTextField="NAME" 
                    HeaderText="Item1" 
                    SortExpression="NAME" />

I want to know how to find the Index of the row in which the Hyperlink is clicked, because I want to change its style, so that the user knows which row was clicked.

OR

How would I change the style of it when the user clicks hyperlink in the gridview.

Thank you.

Answer 1

In your example, the "index" or rather "id" of the hyperlink that was clicked will be in Request.QueryString["id"]

You could compare the ID from the querystring with the ID of the row you are binding to in the RowDataBound event.

Alternatively you could use a <%# DataBinder.Eval %> in your aspx to set the style based upon the ID field and the query string.

EDIT: Code Sample, try adding this to your code behind.

    protected void GridView1_RowDataBound(object sender, GridViewRowEventArgs e)
    {
        if (e.Row.RowType == DataControlRowType.DataRow)
        {
            if(Request.QueryString["id"] != null &&
                Request.QueryString["id"] == DataBinder.Eval(e.Row.DataItem, "id").ToString())
            {
                e.Row.Style.Add("font-weight", "bold");
            }
        }
    }

Answer 2

It is an sample which when you select a row on Gridview child of selected node are shown in the same gridview:

protected void Page_Load(object sender, EventArgs e)
{
    if (!Page.IsPostBack)
    {
        LocationIDHiddenField.Value = Request.QueryString["LocationID"];
    }
    if (LocationIDHiddenField.Value != null && LocationIDHiddenField.Value != string.Empty)
        LoadLocationParents();
}

private void LoadLocationParents()
{
    long locationID = Convert.ToInt64(LocationIDHiddenField.Value);
    bool IsCurrent = true;
    HyperLink parent;        
    Label seperator;
    do
    {
        Basic.Location.LocationProperties location = Basic.Location.LocationLoader.GetLocationProperties(locationID);
        parent = new HyperLink();
        seperator = new Label();
        if (!IsCurrent)  
            parent.NavigateUrl = string.Format("LOCATIONLOV.aspx?LocationID={0}", location.LocationID);
        IsCurrent = false;
        parent.Text = location.LocationTitle;
        seperator.Text = "  >  ";
        ParentsPanel.Controls.AddAt(0, parent);
        ParentsPanel.Controls.AddAt(0, seperator);
        locationID = location.ParentID;     
    }
    while (locationID != 0);
    parent = new HyperLink();
    parent.NavigateUrl = "LOCATIONLOV.aspx";
    parent.Text = "upper nodes";
    ParentsPanel.Controls.AddAt(0, parent);
}

GridView

<asp:GridView ID="ChildsGridView" runat="server" AutoGenerateColumns="False" DataKeyNames="LocationID"
                        DataSourceID="ChildsObjectDataSource" Width="570px" AllowPaging="True">
                        <Columns>
                            <asp:TemplateField>
                                <HeaderTemplate>
                                    &nbsp;
                                </HeaderTemplate>
                                <ItemStyle Width="20px" />
                                <ItemTemplate>
                                    <a onclick="if ('<%# Eval("ChildCount") %>' == 'False') return false;" href='<%# Eval("LocationID", "LOCATIONLOV.aspx?LocationID={0}") %>' ><asp:Image  ID="GridLocationLov" runat="server" ToolTip="Expand" SkinID="LOVChilds" /></a> 
                                </ItemTemplate>
                            </asp:TemplateField>
                            <asp:TemplateField HeaderText="Title" SortExpression="LocationTitleType">
                                <ItemTemplate>
                                    <span class="LOVSelectText" onclick="LOCATIONID = '<%# Eval("LocationID") %>'; LOCATIONTITLE = <%= ConfirmTextBox.ClientID %>.value = '<%# Eval("LocationTitle") %>';ChangeSelectedRow(this);">
                                        <%# Eval("LocationTitleType")%>
                                    </span>
                                </ItemTemplate>
                                <HeaderTemplate>
                                    <asp:Label ID="GridHeadLabel" runat="server" OnLoad="GridHeadLabel_Load"></asp:Label>
                                </HeaderTemplate>
                            </asp:TemplateField>
                        </Columns>
                        <EmptyDataTemplate>
                         NO CHild
                        </EmptyDataTemplate>
                    </asp:GridView>

DataSource

<asp:ObjectDataSource ID="ChildsObjectDataSource" runat="server" OldValuesParameterFormatString="original_{0}"
    SelectMethod="Retrive" TypeName="BASIC.LOCATIONLOV.LOCATIONLOVLoader">
    <SelectParameters>
        <asp:ControlParameter ControlID="LocationIDHiddenField" Name="ParentID" PropertyName="Value"
            Type="Int64" />
        <asp:Parameter DefaultValue="LocationTitle" Name="SortExpression" Type="String" />
    </SelectParameters>
</asp:ObjectDataSource>
<asp:HiddenField ID="LocationIDHiddenField" runat="server" />

JavaScript

function ChangeSelectedRow(sender)
{
    if (SelectedRow != null)
        SelectedRow.style.backgroundColor = OriginalColor;
    SelectedRow = sender.parentElement.parentElement;
    OriginalColor = SelectedRow.style.backgroundColor;
    SelectedRow.style.backgroundColor = 'red';
}