BoundColumn.cs source code in C# .NET

                        Code:
                         / 4.0 / 4.0 / untmp / DEVDIV_TFS / Dev10 / Releases / RTMRel / ndp / fx / src / xsp / System / Web / UI / WebControls / BoundColumn.cs / 1305376 / BoundColumn.cs
                        
                        
                            //------------------------------------------------------------------------------ 
// 
//     Copyright (c) Microsoft Corporation.  All rights reserved.
// 
//----------------------------------------------------------------------------- 

namespace System.Web.UI.WebControls { 
 
    using System;
    using System.Collections; 
    using System.ComponentModel;
    using System.Globalization;
    using System.Web;
    using System.Web.UI; 
    using System.Web.Util;
 
    ///  
    /// Creates a column bounded to a data field in a .
    ///  
    public class BoundColumn : DataGridColumn {


        ///  
        ///    Specifies a string that represents "this". This field is read-only. 
        ///  
        public static readonly string thisExpr = "!"; 

        private PropertyDescriptor boundFieldDesc; 
        private bool boundFieldDescValid;
        private string boundField;
        private string formatting;
 

        ///  
        /// Initializes a new instance of a  class. 
        /// 
        public BoundColumn() { 
        }


 
        /// 
        ///     Gets or sets the field name from the data model bound to this column. 
        ///  
        [
            WebCategory("Data"), 
            DefaultValue(""),
            WebSysDescription(SR.BoundColumn_DataField)
        ]
        public virtual string DataField { 
            get {
                object o = ViewState["DataField"]; 
                if (o != null) 
                    return (string)o;
                return String.Empty; 
            }
            set {
                ViewState["DataField"] = value;
                OnColumnChanged(); 
            }
        } 
 

        ///  
        ///    Gets or sets the display format of data in this
        ///       column.
        /// 
        [ 
            WebCategory("Behavior"),
            DefaultValue(""), 
            WebSysDescription(SR.BoundColumn_DataFormatString) 
        ]
        public virtual string DataFormatString { 
            get {
                object o = ViewState["DataFormatString"];
                if (o != null)
                    return (string)o; 
                return String.Empty;
            } 
            set { 
                ViewState["DataFormatString"] = value;
                OnColumnChanged(); 
            }
        }

 
        /// 
        ///    Gets or sets the property that prevents modification to data 
        ///       in this column. 
        /// 
        [ 
            WebCategory("Behavior"),
            DefaultValue(false),
            WebSysDescription(SR.BoundColumn_ReadOnly)
        ] 
        public virtual bool ReadOnly {
            get { 
                object o = ViewState["ReadOnly"]; 
                if (o != null)
                    return (bool)o; 
                return false;
            }
            set {
                ViewState["ReadOnly"] = value; 
                OnColumnChanged();
            } 
        } 

 

        /// 
        /// 
        protected virtual string FormatDataValue(object dataValue) { 
            string formattedValue = String.Empty;
 
            if (!DataBinder.IsNull(dataValue)) { 
                if (formatting.Length == 0) {
                    formattedValue = dataValue.ToString(); 
                }
                else {
                    formattedValue = String.Format(CultureInfo.CurrentCulture, formatting, dataValue);
                } 
            }
 
            return formattedValue; 
        }
 

        /// 
        /// 
        public override void Initialize() { 
            base.Initialize();
 
            boundFieldDesc = null; 
            boundFieldDescValid = false;
 
            boundField = DataField;
            formatting = DataFormatString;
        }
 

        ///  
        /// Initializes a cell in the DataGridColumn. 
        /// 
        public override void InitializeCell(TableCell cell, int columnIndex, ListItemType itemType) { 
            base.InitializeCell(cell, columnIndex, itemType);

            Control childControl = null;
            Control boundControl = null; 

            switch (itemType) { 
                case ListItemType.Header: 
                case ListItemType.Footer:
                    break; 

                case ListItemType.Item:
                case ListItemType.AlternatingItem:
                case ListItemType.SelectedItem: 
                    if (DataField.Length != 0) {
                        boundControl = cell; 
                    } 
                    break;
 
                case ListItemType.EditItem:
                    if (ReadOnly == true) {
                        goto case ListItemType.Item;
                    } 
                    else {
                        // 
                        TextBox editor = new TextBox(); 
                        childControl = editor;
 
                        if (boundField.Length != 0) {
                            boundControl = editor;
                        }
                    } 
                    break;
            } 
 
            if (childControl != null) {
                cell.Controls.Add(childControl); 
            }

            if (boundControl != null) {
                boundControl.DataBinding += new EventHandler(this.OnDataBindColumn); 
            }
        } 
 

        ///  
        /// 
        private void OnDataBindColumn(object sender, EventArgs e) {
            Debug.Assert(DataField.Length != 0, "Shouldn't be DataBinding without a DataField");
 
            Control boundControl = (Control)sender;
            DataGridItem item = (DataGridItem)boundControl.NamingContainer; 
            object dataItem = item.DataItem; 

            if (boundFieldDescValid == false) { 
                if (!boundField.Equals(thisExpr)) {
                    boundFieldDesc = TypeDescriptor.GetProperties(dataItem).Find(boundField, true);
                    if ((boundFieldDesc == null) && !DesignMode) {
                        throw new HttpException(SR.GetString(SR.Field_Not_Found, boundField)); 
                    }
                } 
                boundFieldDescValid = true; 
            }
 
            object data = dataItem;
            string dataValue;

            if ((boundFieldDesc == null) && DesignMode) { 
                dataValue = SR.GetString(SR.Sample_Databound_Text);
            } 
            else { 
                if (boundFieldDesc != null) {
                    data = boundFieldDesc.GetValue(dataItem); 
                }
                dataValue = FormatDataValue(data);
            }
 
            if (boundControl is TableCell) {
                if (dataValue.Length == 0) { 
                    dataValue = " "; 
                }
                ((TableCell)boundControl).Text = dataValue; 
            }
            else {
                Debug.Assert(boundControl is TextBox, "Expected the bound control to be a TextBox");
                ((TextBox)boundControl).Text = dataValue; 
            }
        } 
    } 
}
 

// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
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BoundColumn.cs source code in C# .NET

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