ASP.NET: Extend BoundField Control - Add MultiLine support

Sep 20, 2006  • ASP.NET

I’ve been working with the data controls and it’s somewhat cumbersome to use a TemplateField control every time you want to just have a MultiLine TextBox. So, I decided to extend upon the BoundField control to add MultiLine support. It is actually rather simple to do.

Using the BoundTextBoxField control in the page:

<%@ Register Namespace="CustomBoundField" TagPrefix="custom" %>


<asp:GridView ID="GridView1" runat="server"> <Columns> <custom:BoundTextBoxField DataField="Text" HeaderText="MultiLine Text" SortExpression="Text" TextMode="MultiLine" Rows="5" Columns="25" Wrap="True" /> </Columns> </asp:GridView>

Code for the BoundTextBoxField control (~/App_Code/BoundTextBoxField.cs):

using System;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;

namespace CustomBoundField {

    /// Summary description for BoundTextBoxField ///
    public class BoundTextBoxField : System.Web.UI.WebControls.BoundField {
    public TextBoxMode TextMode { get { TextBoxMode _tm = TextBoxMode.SingleLine; if (this.ViewState["TextMode"] != null) _tm = (TextBoxMode)this.ViewState["TextMode"]; return _tm; } set { this.ViewState["TextMode"] = value; } }
    
    public int Columns { get { int i = 0; if (this.ViewState["Columns"] != null) i = (int)this.ViewState["Columns"]; return i; } set { this.ViewState["Columns"] = value; } }
    
    public int Rows { get { int i = 0; if (this.ViewState["Rows"] != null) i = (int)this.ViewState["Rows"]; return i; } set { this.ViewState["Rows"] = value; } }
    
    public bool Wrap { get { bool b = true; if (this.ViewState["Wrap"] != null) b = (bool)this.ViewState["Wrap"]; return b; } set { this.ViewState["Wrap"] = value; } }
    
    protected override void OnDataBindField(object sender, EventArgs e) { base.OnDataBindField(sender, e); Control c = (Control)sender; if (c is TextBox) { TextBox txt = (TextBox)c; txt.TextMode = this.TextMode; txt.Columns = this.Columns; txt.Rows = this.Rows; txt.Wrap = this.Wrap; }
    }
}

}