mRemoteNG/mRemoteV1/UI/Forms/TextBox.cs

using System;
using System.ComponentModel;
using System.Windows.Forms;

// Adapted from http://stackoverflow.com/a/3678888/2101395

namespace mRemoteNG.UI.Forms
{
	public class TextBox : Controls.Base.NGTextBox
	{
        #region Public Properties
		[Category("Behavior"),
			DefaultValue(false)]private bool _SelectAllOnFocus;
        public bool SelectAllOnFocus
		{
			get => _SelectAllOnFocus;
            set => _SelectAllOnFocus = value;
        }
        #endregion
			
        #region Protected Methods
		protected override void OnEnter(EventArgs e)
		{
			base.OnEnter(e);

            if (MouseButtons != MouseButtons.None) return;
            SelectAll();
            _focusHandled = true;
        }
			
		protected override void OnLeave(EventArgs e)
		{
			base.OnLeave(e);
				
			_focusHandled = false;
		}
			
		protected override void OnMouseUp(MouseEventArgs e)
		{
			base.OnMouseUp(e);

            if (_focusHandled) return;
            if (SelectionLength == 0)
            {
                SelectAll();
            }
            _focusHandled = true;
        }
        #endregion
			
        #region Private Fields
		private bool _focusHandled;
        #endregion

        private void InitializeComponent()
        {
            this.SuspendLayout();
            // 
            // TextBox
            // 
            this.Font = new System.Drawing.Font("Segoe UI", 8.25F, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, ((byte)(0)));
            this.ResumeLayout(false);

        }
    }
}