TableLayoutPanel: Delete Rows

gbbb picture gbbb · Apr 25, 2013 · Viewed 12.5k times · Source

I have a TableLayoutPanel which is filled with rows at runtime using a text file (get each row from the text file, and put it in cells contained in new rows). Code Looks like this:

public static string UrlList= @"C:\Users\Berisha\Desktop\URLs.txt";
string[] UrlRows = System.IO.File.ReadAllLines(@UrlList);
        private void InitPaths()
    {
        int a = 0;
        int c = 1;
        while (a < UrlRows.Length-1)
        {   
            //new label
            var label = new Label();
            label.Dock = DockStyle.Fill;
            label.AutoSize = false;
            label.Text = UrlRows[a];
            label.TextAlign = System.Drawing.ContentAlignment.MiddleLeft;
            label.Size = new System.Drawing.Size(22, 13);
            label.BackColor = System.Drawing.Color.Transparent;
            TBP.Controls.Add(label, 3, c); //Add to TableLayoutPanel
            a++;
            c++;
        }
    }

Although I want to be able to manually edit the source, so I wrote a method which would delete everything new created, but seem to be stuck here, because it doesn't work:

        private void clearPaths()
    {   
        int c = UrlRows.Length - 1;
        while (c <= UrlRows.Length - 1)
        {
            TBP.RowStyles.RemoveAt(c); //Remove from TableLayoutPanel
            c--;
        }

    }

//The Code Stops at: TableLayoutPanel.RowStyles.RemoveAt(c);(while Debugging) //and the error reads : "Object reference not set to an instance of an object" Update: I managed to get out of the Error, my Problem now, after I say RemoveAt, nothing seems to be removed Does anybody know what it is that I could do?

Answer

Arm0geddon picture Arm0geddon · Oct 31, 2013

I Googled and Binged a solution to this problem for DAYS and couldn't find one. I finally came with a solution that works!

tableLayoutPanel.SuspendLayout();

while (tableLayoutPanel.RowCount > 1)
{
    int row = tableLayoutPanel.RowCount - 1;
    for (int i = 0; i < tableLayoutPanel.ColumnCount; i++)
    {
        Control c = tableLayoutPanel.GetControlFromPosition(i, row);
        tableLayoutPanel.Controls.Remove(c);
        c.Dispose();
    }

    tableLayoutPanel.RowStyles.RemoveAt(row);
    tableLayoutPanel.RowCount--;
}

tableLayoutPanel.ResumeLayout(false);
tableLayoutPanel.PerformLayout();

In my solution, I do not want to remove the first row.