CODEWITHSUNDEEP
c#asp.netgridview
Perry
Perry

Reputation: 1337

Save data record and Hide an ASP.net Gridview button after onclick

I have a gridview with an asp.net button that calls a C# method to update a database based on some data within the gridview row. That method gets the rowindex and the values to update the data record. I then want to hide the button for that row. I am using the code shown below:

protected void AddJacket_Click(object sender, EventArgs e)
    {
        //Determine the RowIndex of the Row whose Button was clicked.
        int rowIndex = ((sender as Button).NamingContainer as GridViewRow).RowIndex;

        //Get the value of column from the DataKeys using the RowIndex.
        int id1 = Convert.ToInt32(GridViewSubjectList.DataKeys[rowIndex].Values[0]);
        int id2 = Convert.ToInt32(GridViewSubjectList.DataKeys[rowIndex].Values[1]);

        using (CADWEntities db = new CADWEntities())
        {
            var results = db.Subjects.SingleOrDefault(uu => uu.SubjectId == id1);
            results.JacketNumber = Convert.ToString(id2);
            db.SaveChanges();

        }

        //Hide the button after being click
        Button Button = GridViewSubjectList.SelectedRow.Cells[0].FindControl("btnAddJacket") as Button;
        Button.Enabled = false;
        Button.Visible = false;
    }

I get this error message {"Object reference not set to an instance of an object."} on the first line of code that hides the button.

If I use the same code for a method OnSelectedIndexChange and change the button to a LinkButton the code for hiding the link works but the code to update the database fails.

How can I get this code to work together?

Thanks

Upvotes: 0

Views: 989

Answers (1)

Enrique Zavaleta
Enrique Zavaleta

Reputation: 2108

You just need to cast the sender to a Control and set it to visible = false

protected void AddJacket_Click(object sender, EventArgs e)
{
    //Determine the RowIndex of the Row whose Button was clicked.
    int rowIndex = ((sender as Button).NamingContainer as GridViewRow).RowIndex;

    //Get the value of column from the DataKeys using the RowIndex.
    int id1 = Convert.ToInt32(GridViewSubjectList.DataKeys[rowIndex].Values[0]);
    int id2 = Convert.ToInt32(GridViewSubjectList.DataKeys[rowIndex].Values[1]);

    using (CADWEntities db = new CADWEntities())
    {
        var results = db.Subjects.SingleOrDefault(uu => uu.SubjectId == id1);
        results.JacketNumber = Convert.ToString(id2);
        db.SaveChanges();

    }

    //Hide the button after being click
    (sender as Control).Visible = false;
}

Note: The sender is the control that raise the event, also, I'm casting the sender to a Control because no matter if it is a Button, LinkButton, etc it will work for any Control that has a Visible property

Upvotes: 1

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