TableLayoutPanel的行高不正确

Question

I have auto-sized 2x2 table layout and long auto-sized labels in each cell. This layout is in other table layout with no-auto-sized cells. Minimal project to reproduce the problem:

using System;
using System.Windows.Forms;

namespace TestForms {
    static class Program {
        [STAThread]
        static void Main() {
            Application.EnableVisualStyles();
            Application.SetCompatibleTextRenderingDefault(false);
            Application.Run(new TestForm());
        }
    }

    class TestForm : Form {
        public TestForm() {
            var childPanel = new TableLayoutPanel();
            var label8 = new Label();
            var label9 = new Label();
            var label10 = new Label();
            var label7 = new Label();
            var rootPanel = new TableLayoutPanel();

            childPanel.AutoSize = true;
            childPanel.AutoSizeMode = AutoSizeMode.GrowAndShrink;
            childPanel.BackColor = System.Drawing.Color.Silver;
            childPanel.ColumnCount = 2;
            childPanel.ColumnStyles.Add(new ColumnStyle(SizeType.Percent, 50F));
            childPanel.ColumnStyles.Add(new ColumnStyle(SizeType.Percent, 50F));
            childPanel.Controls.Add(label8, 1, 0);
            childPanel.Controls.Add(label9, 0, 1);
            childPanel.Controls.Add(label10, 1, 1);
            childPanel.Controls.Add(label7, 0, 0);
            childPanel.Dock = DockStyle.Top;
            childPanel.RowCount = 2;
            childPanel.RowStyles.Add(new RowStyle());
            childPanel.RowStyles.Add(new RowStyle());

            label8.AutoSize = true;
            label8.Text = "2ggggggggggggggggg";

            label9.AutoSize = true;
            label9.Text = "label9";

            label10.AutoSize = true;
            label10.Text = "label10";

            label7.AutoSize = true;
            label7.Text = "label7";

            rootPanel.ColumnCount = 1;
            rootPanel.ColumnStyles.Add(new ColumnStyle(SizeType.Percent, 100F));
            rootPanel.Controls.Add(childPanel, 0, 0);
            rootPanel.Dock = DockStyle.Fill;
            rootPanel.RowCount = 1;
            rootPanel.RowStyles.Add(new RowStyle(SizeType.Percent, 100F));

            ClientSize = new System.Drawing.Size(205, 197);
            Controls.Add(rootPanel);
        }
    }
}

I get the following result:

Why last row got the wrong height? Is there a workaround?

Answer 1

Interestingly, seems like you have hit some bug since it doesn't happen if some of the labels AutoSize is false , or making the first column style SizeType.AutoSize etc.

You can use the following workaround. It's ugly, but that's the only way I've found. The idea is to add invisible row containing fake Label with AutoSize set to false . For instance, after setting up the normal layout, add the following lines:

childPanel.RowCount++;
childPanel.RowStyles.Add(new RowStyle(SizeType.Absolute, 0));
childPanel.Controls.Add(new Label { AutoSize = false }, 0, childPanel.RowCount - 1);