c# dropdownlist selectedindexchanged in gridview sets selectedindex of second dropdownlist

Question

I have a gridview with two dropdownlists populated from a db. One is a descriptive name, the other is an abbreviated name. I need to accomplish the following:

When I select an item in DDL1 I need to change the selected index of DDL2 to match, and vice versa.

I have searched on here and found the following:

protected void ddlAddLabTest_SelectedIndexChanged(object sender, EventArgs e)
{
   DropDownList ddlLabTest = (DropDownList)sender;
   GridViewRow row = (GridViewRow)ddlLabTest.NamingContainer;
   DropDownList ddlAddLabTestShortName = (DropDownList)row.FindControl("ddlAddShortname");

   ddlAddLabTestShortName.SelectedIndex = intSelectedIndex;
}

Only when it gets to the assignment for "row" I receive the following:

Unable to cast object of type 'System.Web.UI.WebControls.DataGridItem' to type 'System.Web.UI.WebControls.GridViewRow'.

I have tried finding a working example but I can't. Any help is greatly appreciated!

Have you tried a javascript solution or do you need to postback? If the DDLs are always going to equal eachother, why do you need both? — MikeSmithDev, Nov 12 '12 at 20:45

score 6 · Accepted Answer · answered Nov 12 '12 at 21:08

6

Try this

protected void ddlAddLabTest_SelectedIndexChanged(object sender, EventArgs e)
{
   DropDownList ddlLabTest = (DropDownList)sender;
   DataGridItem row = (DataGridItem) ddlLabTest.NamingContainer;
   DropDownList ddlAddLabTestShortName = (DropDownList)row.FindControl("ddlAddShortname");

   ddlAddLabTestShortName.SelectedIndex = intSelectedIndex;
}

answered Nov 12 '12 at 21:08

codingbiz

26,179
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Thanks a lot! I had to use _GridViewRow_ instead of _DataGridItem_ But it worked! :) – divinediu Apr 03 '14 at 04:47

score 1 · Answer 2 · answered Nov 12 '12 at 20:43

1

Seems like the NamingContainer is not a row, so leave it like that. It already has the FindControl method.

var row = ddlLabTest.NamingContainer;

answered Nov 12 '12 at 20:43

Amiram Korach

13,056
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Tried that: "Cannot implicitly convert type 'System.Web.UI.Controls' to 'System.Web.UI.WebControls.GridViewRow'. An explicit conversion exists (are you missing a cast?)" – NJohns Nov 12 '12 at 20:51
1

Remove the GridViewRow type. Use var. – Amiram Korach Nov 12 '12 at 20:54

c# dropdownlist selectedindexchanged in gridview sets selectedindex of second dropdownlist

2 Answers2