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c#winformsdatagridview

I can‘t close the Form when I try to add code to manipulate the DataGridView in a WinForms application，and there are no compiler error messages

I'm trying to develop a WinForms application using C#. I'm using the DataGridView component and I want to add a column when a button is pressed. Additionally, when the mouse focus leaves the current area, I want to check if there are any empty cells in the DataGridView. If there are, I want to automatically delete the column containing that cell and sort the DataGridView. Here is my Code:

private void dataGridView4_Leave(object sender, EventArgs e)
{
    // Create a list to store columns to be removed
    List<DataGridViewColumn> columnsToRemove = new List<DataGridViewColumn>();

    // Iterate through each column in the DataGridView (starting from index 1, skipping the first column)
    for (int i = dataGridView4.Columns.Count - 1; i >= 1; i--)
    {
        DataGridViewColumn column = dataGridView4.Columns[i];
        bool isEmpty = true;

        // Iterate through all cells in the current column
        foreach (DataGridViewRow row in dataGridView4.Rows)
        {
            // Check if the cell is empty
            if (row.Cells[column.Index].Value != null && !string.IsNullOrWhiteSpace(row.Cells[column.Index].Value.ToString()))
            {
                // If at least one cell is not empty, set isEmpty to false and break out of the inner loop
                isEmpty = false;
                break;
            }
        }

        // If all cells in the current column are empty, add the column to the list of columns to be removed
        if (isEmpty)
        {
            columnsToRemove.Add(column);
        }
    }

        // Remove the columns
        foreach (var columnToRemove in columnsToRemove)
        {
            dataGridView4.Columns.Remove(columnToRemove);
        }

    // Refresh the dataGridView and rename/reorder the columns
    RefreshDataGridViewIndex();
}

enter image description here

When I leave the area, there is no more blank columns, but I can't Close this Form. enter image description here

The compiler doesn't provide any relevant error messages, but I can't close the Form. I don't know why this is happening. Can someone help me?

What's more, the following situation can also prevent me from closing the current Form.enter image description here

After Trigger this code: enter image description here

In fact, this is exactly the effect I want this piece of code to achieve, that is, to delete the column to which the empty cell belongs when it exists. I hope this situation can provide more clues to help you locate the problem.

I tried to debug by reverse outputting or adding MessageBox.Show to locate where is the bug, but since the compiler didn't give me any clear error messages, I find it difficult to proceed. I can use other way or just give up my idea, but I just want to know why this happened.

---------------------------new clue------------------------ I just discovered a new clue, but I don't understand the mechanism behind the issue. The layout of my controls is as shown in the figure below. enter image description here Previously, I bound private void dataGridView4_Leave(object sender, EventArgs e) to the GroupBox instead of the DataGridView because I didn't want the behavior of clearing empty columns to trigger when I clicked on the GroupBox. I bound the event to the GroupBox's Leave event. enter image description here However, now that I've unbound the Leave event from the GroupBox and instead bound private void dataGridView4_Leave(object sender, EventArgs e) to the Mouse_Leave event of my DataGridView, it miraculously works correctly. enter image description here I'm wondering why this is the case. Are there any differences in the processing logic between the Leave event and Mouse_Leave event that would prevent me from closing my Form? I hope someone can help clarify my confusion. Thank you!

Solution

  • This might do SOMETHING but it feel very dirty

    protected override void OnFormClosing(FormClosingEventArgs e) 
{ 
    e.Cancel = false;
    base.OnFormClosing(e);
}