Get GridView selected row DataKey in Javascript - asp.net

Question

I have GridView which I can select a row. I then have a button above the grid called Edit which the user can click to popup a window and edit the selected row. So the button will have Javascript code behind it along the lines of
function editRecord()
{
var gridView = document.getElementById("<%= GridView.ClientID %>");
var id = // somehow get the id here ???
window.open("edit.aspx?id=" + id);
}
The question is how do I retrieve the selected records ID in javascript?

Answer 1

I worked it out based on JasonS response. What I did was create a hidden field in the Grid View like this:
<asp:TemplateField ShowHeader="False">
<ItemTemplate>
<asp:HiddenField ID="hdID" runat="server" Value='<%# Eval("JobID") %>' />
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField Visible="False">
<ItemTemplate>
<asp:LinkButton ID="lnkSelect" runat="server" CommandName="select" Text="Select" />
</ItemTemplate>
</asp:TemplateField>
Then on the OnRowDataBind have code to set the selected row
protected virtual void Grid_RowDataBound(object sender, GridViewRowEventArgs e)
{
if (e.Row.RowType == DataControlRowType.DataRow)
{
// Click to highlight row
Control lnkSelect = e.Row.FindControl("lnkSelect");
if (lnkSelect != null)
{
StringBuilder click = new StringBuilder();
click.AppendLine(m_View.Page.ClientScript.GetPostBackClientHyperlink(lnkSelect, String.Empty));
click.AppendLine(String.Format("onGridViewRowSelected('{0}')", e.Row.RowIndex));
e.Row.Attributes.Add("onclick", click.ToString());
}
}
}
And then in the Javascript I have code like this
<script type="text/javascript">
var selectedRowIndex = null;
function onGridViewRowSelected(rowIndex)
{
selectedRowIndex = rowIndex;
}
function editItem()
{
if (selectedRowIndex == null) return;
var gridView = document.getElementById('<%= GridView1.ClientID %>');
var cell = gridView.rows[parseInt(selectedRowIndex)+1].cells[0];
var hidID = cell.childNodes[0];
window.open('JobTypeEdit.aspx?id=' + hidID.value);
}
</script>
Works a treat :-)

Answer 2

1) change your javascript function to use a parameter
function editRecord(clientId)
{ ....
2) output the call in your editRecord button... if you want to avoid dealing with the .net generated ids, just use a simple
<input type="button" onclick="editRecord(your-rows-client-id-goes-here)" />

Answer 3

Based off of your comments to #DaveK's response, in javascript you can set the id of a hidden field to the clientId of the selected row when the user selects it. Then have your editRecord function use the value set on the hidden form field.

Answer 4

one could avoid javascript altogether, by setting anchor tags pre-populated with the query string for each row (although this will effect your table layout, it will need only one click rather than 2 from the user)
insert in the gridview template:
<asp:HyperLink runat="server" ID="editLink" Target="_blank"
NavigateURL='<%# Eval("JobID","edit.aspx?id={0}") %>'>
Edit..
</asp:HyperLink>