Zeta .NET Base Libraries

namespace ZetaLib.Web.Base
{
	#region Using directives.
	// ----------------------------------------------------------------------

	using System;
	using System.Diagnostics;
	using System.Web.UI;
	using ZetaLib.Web.Common;
	using ZetaLib.Core.Logging;
	using ZetaLib.Web.Properties;
	using System.Web.UI.HtmlControls;
	using ZetaLib.Web.Controls;

	// ----------------------------------------------------------------------
	#endregion

	/////////////////////////////////////////////////////////////////////////

	/// <summary>
	/// Base class for user controls.
	/// </summary>
	public class UserControlBase :
		UserControl
	{
		#region Testing whether JavaScript is enabled.
		// ------------------------------------------------------------------

		/// <summary>
		/// Set to true to enable checking whether JavaScript is enabled.
		/// Does a postback if turned on.
		/// </summary>
		/// <value>
		/// 	<c>true</c> if [want test java script enabled]; otherwise, <c>false</c>.
		/// </value>
		protected bool WantTestJavaScriptEnabled
		{
			get
			{
				return wantTestJavaScriptEnabled;
			}

			set
			{
				wantTestJavaScriptEnabled = value;

				if ( value )
				{
					javaScriptTester = new JavascriptTest();
					this.Controls.Add( javaScriptTester );
				}
				else
				{
					if ( javaScriptTester != null )
					{
						this.Controls.Remove( javaScriptTester );
						javaScriptTester = null;
					}
				}
			}
		}

		private bool wantTestJavaScriptEnabled = false;

		/// <summary>
		/// Checks whether JavaScript is enabled on the client.
		/// </summary>
		/// <value>
		/// 	<c>true</c> if this instance is java script enabled; otherwise, <c>false</c>.
		/// </value>
		protected bool IsJavaScriptEnabled
		{
			get
			{
				object o = Session[@"IsJavaScriptEnabled"];

				if ( o == null )
				{
					if ( !wantTestJavaScriptEnabled )
					{
						throw new ArgumentException(
							string.Format(
							Resources.Str_ZetaLib_Web_Base_UserControlBase_01 ) );
					}
					else
					{
						bool b = javaScriptTester.Enabled;

						if ( IsPostBack )
						{
							Session[@"IsJavaScriptEnabled"] = b;
						}
						return b;
					}
				}
				else
				{
					bool b = Convert.ToBoolean( o );
					return b;
				}
			}
		}

		private JavascriptTest javaScriptTester = null;

		// ------------------------------------------------------------------
		#endregion

		#region Overrides.
		// ------------------------------------------------------------------

		/// <summary>
		/// Raises the <see cref="E:System.Web.UI.Control.Load"></see> event.
		/// </summary>
		/// <param name="e">The <see cref="T:System.EventArgs"></see> object that contains the event data.</param>
		protected override void OnLoad(
			EventArgs e )
		{
			base.OnLoad( e );

			if ( (Page is PageBase) &&
				((PageBase)Page).AutoDataBind )
			{
				LogCentral.Current.LogDebug(
					@"Databinding in ZetaLib.Web.Base.UserControlBase.OnLoad(), " +
					@"because ZetaLib.Web.Base.PageBase.AutoDataBind is true." );

				DataBind();
			}
		}

		/// <summary>
		/// Handles the pressing of the [enter] key on a textbox,
		/// to automatically submit the form.
		/// </summary>
		/// <param name="button">The button.</param>
		/// <returns></returns>
		/// <remarks>
		/// To use this function, simply add the following attribute to
		/// a textbox inside the .ASPX file:
		/// OnKeyDown='GlobalKeyDownEnterHandler(CmdSubmit)'
		/// Where "CmdSubmit" is the ID of the button to press upon [enter].
		/// </remarks>
		protected string GlobalKeyDownEnterHandler(
			Control button )
		{
			return string.Format(
				@"GlobalKeyDownEnterHandler( {0} )",
				button.ClientID );
		}

		// ------------------------------------------------------------------
		#endregion

		#region Public properties.
		// ------------------------------------------------------------------

		/// <summary>
		/// Provides access to an enhanced version of the query string parameters.
		/// </summary>
		/// <value>The QS.</value>
		public QueryString QS
		{
			get
			{
				// I must not create a separate instance but must
				// use the same QS object as the page.
				if ( Page != null && Page is PageBase )
				{
					return ((PageBase)Page).QS;
				}
				else
				{
					return null;
				}
			}
		}

		/// <summary>
		/// Access an instance of the web cache.
		/// </summary>
		/// <value>The page cache.</value>
		public System.Web.Caching.Cache PageCache
		{
			get
			{
				if ( Page != null && Page is PageBase )
				{
					return ((PageBase)Page).PageCache;
				}
				else
				{
					return null;
				}
			}
		}

		/// <summary>
		/// Provides access to the resource manager, that enables to load
		/// multilingual strings from the database.
		/// </summary>
		/// <value>The res man.</value>
		public DBStringResourceManagerBase ResMan
		{
			get
			{
				Debug.Assert(
					Page != null && Page is PageBase,
					@"Page is either NULL or not derived from PageBase." );
				return ((PageBase)Page).ResMan;
			}
		}

		/// <summary>
		/// Get/set the text that appears as an error text on the page.
		/// </summary>
		/// <value>The error text.</value>
		public virtual string ErrorText
		{
			get
			{
				return ErrorTextControl.InnerHtml;
			}
			set
			{
				string s = value;

				ErrorTextControl.InnerHtml = s;
				ErrorTextControl.Visible =
					ErrorTextControl.InnerHtml.Length > 0;
			}
		}

		/// <summary>
		/// Tries to locate a control with the ID 'ErrorTextControl' on
		/// the current page.
		/// </summary>
		/// <value>The error text control.</value>
		public virtual HtmlGenericControl ErrorTextControl
		{
			get
			{
				return (Page as PageBase).ErrorTextControl;
			}
		}

		// ------------------------------------------------------------------
		#endregion
	}

	/////////////////////////////////////////////////////////////////////////
}