为什么无法在Method中访问数据？

Question

I'm currently trying to fill a TableLayoutPanel through a method which goes as follows:

private int _rowCount;
public void InitPaths()
{
    int c = 1;
    int a = 1;

    while (a < _PathRows.Length - 1)
    {
        var label = new Label();
        //
        // Label - Format.
        //
        label.Dock = DockStyle.Fill;
        label.AutoSize = false;
        label.Text = _pfadZeilen[a];
        label.TextAlign = System.Drawing.ContentAlignment.MiddleLeft;
        label.Size = new System.Drawing.Size(22, 13);
        label.BackColor = System.Drawing.Color.Transparent;
        TableLayoutP.Controls.Add(label, 3, c);

        //Checkboxen Einfügen
        var cbox = new CheckBox();
        //
        //Checkbox Format.
        cbox.Anchor = System.Windows.Forms.AnchorStyles.None;
        cbox.AutoSize = true;
        cbox.CheckAlign = System.Drawing.ContentAlignment.MiddleCenter;
        cbox.Name = "checkBoxPfad" + a;
        cbox.Size = new System.Drawing.Size(15, 14);
        cbox.TextAlign = System.Drawing.ContentAlignment.MiddleCenter;
        cbox.UseVisualStyleBackColor = true;
        TableLayoutP.Controls.Add(cbox, 0, c);
        a++;
        c++;

    }

    this._rowCount = BibTable.GetRowHeights().Length; // which seems to be Holding the value only within the method
}

and then delete all rows on Action, through the following Method:

public void RemoveRows()
{
    for (int row = _rowCount; row >= 0; row--)
    {
        BibTable.RowStyles.RemoveAt(row);
        BibTable.RowCount--;
    }
}

Now the Problem is, if I try to do anything with the TableLayoutP outside of the method where all rows are initialized, it will tell me:

Object reference not set to the instance of an object.

What can I do? Is there a way to get a method inside a method (I'm realising just how stupid that sounds while typing it) or any other way to deal with this Situation?

Answer 1

You are ittering through GetRowHeights() , returning the height of each row. But you are deleting from the RowStyles collection which is not directly related to the first collection. I assume that GetRowHeights() returns much more rows, than RowStyles has.

Why not:

BibTable.RowCount = 0;
BibTable.RowStyles.Clear();

Answer 2

You are ittering through GetRowHeights() , returning the height of each row. But you are deleting from the RowStyles collection which is not directly related to the first collection. I assume that GetRowHeights() returns much more rows, than RowStyles has.

Why not:

BibTable.RowCount = 0;
BibTable.RowStyles.Clear();