xenadmin/XenAdmin/Controls/Common/AutoHeightLabel.cs

/* Copyright (c) Citrix Systems, Inc. 
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using System;
using System.Drawing;
using System.Windows.Forms;

namespace XenAdmin.Controls.Common
{
    /// <summary>
    /// A label which automatically changes its height to accomodate its <see cref="Label.Text"/> when in AutoSize mode. This is useful 
    /// as it enables a multi-line label to be put in a <see cref="TableLayoutPanel"/> - the table can then be made to vertically shrink/grow 
    /// depending on the label text. 
    /// </summary>
    public partial class AutoHeightLabel : Label
    {
        private const TextFormatFlags _flags = TextFormatFlags.WordBreak;
        private const int _maxHeight = 9999;

        public AutoHeightLabel()
        {
            InitializeComponent();
        }

        protected override void OnHandleCreated(EventArgs e)
        {
            base.OnHandleCreated(e);
            using (var g = Graphics.FromHwnd(Handle))
            {
                var textSize = TextRenderer.MeasureText(g, Text, Font, new Size(Width - Padding.Left - Padding.Right, _maxHeight), _flags);
                Height = textSize.Height + Padding.Top + Padding.Bottom;
            }
        }

        public override Size GetPreferredSize(Size proposedSize)
        {
            using (var g = Graphics.FromHwnd(Handle))
            {
                var textSize = TextRenderer.MeasureText(g, Text, Font, new Size(proposedSize.Width - Padding.Left - Padding.Right, _maxHeight), _flags);
                return new Size(Width, textSize.Height + Padding.Top + Padding.Bottom);
            }
        }
    }
}