path: root/mcs/class/System.Web/System.Web.UI.WebControls/BoundField.cs

//
// System.Web.UI.WebControls.BoundField.cs
//
// Authors:
//	Lluis Sanchez Gual (lluis@novell.com)
//
// (C) 2005-2010 Novell, Inc (http://www.novell.com)
//

//
// Permission is hereby granted, free of charge, to any person obtaining
// a copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to
// permit persons to whom the Software is furnished to do so, subject to
// the following conditions:
// 
// The above copyright notice and this permission notice shall be
// included in all copies or substantial portions of the Software.
// 
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
//

using System.Collections;
using System.Collections.Specialized;
using System.Web.UI;
using System.ComponentModel;
using System.Security.Permissions;
using System.Reflection;

namespace System.Web.UI.WebControls
{
	[AspNetHostingPermissionAttribute (SecurityAction.LinkDemand, Level = AspNetHostingPermissionLevel.Minimal)]
	[AspNetHostingPermissionAttribute (SecurityAction.InheritanceDemand, Level = AspNetHostingPermissionLevel.Minimal)]
	public class BoundField : DataControlField
	{
		public static readonly string ThisExpression = "!";
		
		//PropertyDescriptor boundProperty;

		[DefaultValueAttribute (false)]
		[WebSysDescription ("")]
		[WebCategoryAttribute ("Behavior")]
		public virtual bool ApplyFormatInEditMode {
			get { return ViewState.GetBool ("ApplyFormatInEditMode", false); }
			set { ViewState ["ApplyFormatInEditMode"] = value; }
		}
		
		[DefaultValueAttribute (true)]
		[WebSysDescription ("")]
		[WebCategoryAttribute ("Behavior")]
		public virtual bool ConvertEmptyStringToNull {
			get { return ViewState.GetBool ("ConvertEmptyStringToNull", true); }
			set {
				ViewState ["ConvertEmptyStringToNull"] = value;
				OnFieldChanged ();
			}
		}

		[TypeConverterAttribute ("System.Web.UI.Design.DataSourceViewSchemaConverter, " + Consts.AssemblySystem_Design)]
		[WebSysDescription ("")]
		[WebCategoryAttribute ("Data")]
		[DefaultValueAttribute ("")]
		public virtual string DataField {
			get { return ViewState.GetString ("DataField", String.Empty); }
			set {
				ViewState ["DataField"] = value;
				OnFieldChanged ();
			}
		}

		[DefaultValueAttribute ("")]
		[WebSysDescription ("")]
		[WebCategoryAttribute ("Data")]
		public virtual string DataFormatString {
			get { return ViewState.GetString ("DataFormatString", String.Empty); }
			set {
				ViewState ["DataFormatString"] = value;
				OnFieldChanged ();
			}
		}

		[WebSysDescription ("")]
		[WebCategoryAttribute ("Appearance")]
		public override string HeaderText {
			get { return ViewState.GetString ("HeaderText", String.Empty); }
			set {
				ViewState["HeaderText"] = value;
				OnFieldChanged ();
			}
		}

		[DefaultValueAttribute ("")]
		[WebCategoryAttribute ("Behavior")]
		public virtual string NullDisplayText {
			get { return ViewState.GetString ("NullDisplayText", String.Empty); }
			set {
				ViewState ["NullDisplayText"] = value;
				OnFieldChanged ();
			}
		}

		[DefaultValueAttribute (false)]
		[WebSysDescription ("")]
		[WebCategoryAttribute ("Behavior")]
		public virtual bool ReadOnly {
			get { return ViewState.GetBool ("ReadOnly", false); }
			set { 
				ViewState ["ReadOnly"] = value;
				OnFieldChanged ();
			}
		}

		[DefaultValueAttribute (true)]
		[WebSysDescription ("")]
		[WebCategoryAttribute ("HtmlEncode")]
		public virtual bool HtmlEncode {
			get { return ViewState.GetBool ("HtmlEncode", true); }
			set { 
				ViewState ["HtmlEncode"] = value;
				OnFieldChanged ();
			}
		}

		[DefaultValue (true)]
		public virtual bool HtmlEncodeFormatString {
			get { return ViewState.GetBool ("HtmlEncodeFormatString", true); }
			set {
				ViewState ["HtmlEncodeFormatString"] = value;
				OnFieldChanged ();
			}
		}
		
		public override void ExtractValuesFromCell (IOrderedDictionary dictionary,
			DataControlFieldCell cell, DataControlRowState rowState, bool includeReadOnly)
		{
			bool editable = IsEditable (rowState);
			if (editable) {
				if (cell.Controls.Count > 0) {
					TextBox box = (TextBox) cell.Controls [0];
					dictionary [DataField] = box.Text;
				}
			} else if (includeReadOnly)
				dictionary [DataField] = cell.Text;
		}

		public override bool Initialize (bool enableSorting, Control control)
		{
			return base.Initialize (enableSorting, control);
		}

		public override void InitializeCell (DataControlFieldCell cell,
			DataControlCellType cellType, DataControlRowState rowState, int rowIndex)
		{
			base.InitializeCell (cell, cellType, rowState, rowIndex);
			if (cellType == DataControlCellType.DataCell) {
				InitializeDataCell (cell, rowState);
				if ((rowState & DataControlRowState.Insert) == 0)
					cell.DataBinding += new EventHandler (OnDataBindField);
			}
		}
		
		protected virtual void InitializeDataCell (DataControlFieldCell cell, DataControlRowState rowState)
		{
			bool editable = IsEditable (rowState);
			if (editable) {
				TextBox box = new TextBox ();
				cell.Controls.Add (box);
				box.ToolTip = HeaderText;
			}
		}

		internal bool IsEditable (DataControlRowState rowState)
		{
			return ((rowState & DataControlRowState.Edit) != 0 && !ReadOnly) || ((rowState & DataControlRowState.Insert) != 0 && InsertVisible);
		}

		protected virtual bool SupportsHtmlEncode {
			get { return true; }
		}
		
		protected virtual string FormatDataValue (object value, bool encode)
		{
			string res;
			bool htmlEncodeFormatString = HtmlEncodeFormatString;
			string stringValue = (value != null) ? value.ToString () : String.Empty;
			if (value == null || (stringValue.Length == 0 && ConvertEmptyStringToNull)) {
				if (NullDisplayText.Length == 0) {
					encode = false;
					res = " ";
				} else
					res = NullDisplayText;
			} else {
				string format = DataFormatString;
				if (!String.IsNullOrEmpty (format)) {
					if (!encode || htmlEncodeFormatString)
						res = String.Format (format, value);
					else
						res = String.Format (format, encode ? HttpUtility.HtmlEncode (stringValue) : stringValue);
				} else
					res = stringValue;
			}
			
			if (encode && htmlEncodeFormatString)
				return HttpUtility.HtmlEncode (res);
			else
				return res;
		}
		
		protected virtual object GetValue (Control controlContainer)
		{
			if (DesignMode)
				return GetDesignTimeValue ();
			else
				return GetBoundValue (controlContainer);
		}
		
		protected virtual object GetDesignTimeValue ()
		{
			return "Databound";
		}

		object GetBoundValue (Control controlContainer)
		{
			object dataItem = DataBinder.GetDataItem (controlContainer);
			if (dataItem == null)
				throw new HttpException ("A data item was not found in the container. The container must either implement IDataItemContainer, or have a property named DataItem.");

			if (DataField == ThisExpression)
				return dataItem;
			else if (DataField == string.Empty)
				return null;

			return DataBinder.GetPropertyValue (dataItem, DataField);
		}
		
		protected override void LoadViewState (object state)
		{
			// Why override?
			base.LoadViewState (state);
		}
		
		protected virtual void OnDataBindField (object sender, EventArgs e)
		{
			Control container = (Control) sender;
			Control controlContainer = container.BindingContainer;
			if (!(controlContainer is INamingContainer))
				throw new HttpException ("A DataControlField must be within an INamingContainer.");
			object val = GetValue (controlContainer);
			TextBox box = sender as TextBox;

			if (box == null) {
				var cell = sender as DataControlFieldCell;
				if (cell != null) {
					ControlCollection controls = cell.Controls;
					int ccount = controls != null ? controls.Count : 0;
					if (ccount == 1)
						box = controls [0] as TextBox;
					if (box == null) {
						cell.Text = FormatDataValue (val, SupportsHtmlEncode && HtmlEncode);
						return;
					}
				}
			}

			if (box == null)
				throw new HttpException ("Bound field " + DataField + " contains a control that isn't a TextBox.  Override OnDataBindField to inherit from BoundField and add different controls.");
			if (ApplyFormatInEditMode)
				box.Text = FormatDataValue (val, SupportsHtmlEncode && HtmlEncode);
			else
				box.Text = val != null ? val.ToString() : NullDisplayText;
		}
		
		protected override DataControlField CreateField ()
		{
			return new BoundField ();
		}
		
		protected override void CopyProperties (DataControlField newField)
		{
			base.CopyProperties (newField);
			BoundField field = (BoundField) newField;
			field.ConvertEmptyStringToNull = ConvertEmptyStringToNull;
			field.DataField = DataField;
			field.DataFormatString = DataFormatString;
			field.NullDisplayText = NullDisplayText;
			field.ReadOnly = ReadOnly;
			field.HtmlEncode = HtmlEncode;
		}

		// MSDN: The ValidateSupportsCallback method is a helper method used to determine 
		// whether the controls contained in a BoundField object support callbacks. 
		// This method has been implemented as an empty method (a method that does not contain 
		// any code) to indicate that callbacks are supported.
		public override void ValidateSupportsCallback ()
		{
		}

	}
}