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Updated: 06:19 PM CT Jan 09, 2007 Posted: 05:36 PM CT Jan 09, 2007 Set Initial Focus on an ASP.NET Page Easily generate the Javascript to set focus to any control on your ASP.NET page Author: Steve Lautenschlager Snippet C# Javascript Browsers Client Side Web  Summary Setting the cursor focus to a particular element of a web page when it loads is a pretty common little feature, but it can be annoying to implement. Here I automated the process in a C# method. You only need to pass the Control to the method and it will register the Javascript and set focus on page load. This code was adapted from work by Fons.Sonnemans@reflectionit.nl. Setup a couple of text boxes to test by adding the following to your aspx page. Example: How to use the SetInitialFocus method <P><asp:TextBox id="TextBox1" runat="server"></asp:TextBox> <P><INPUT id="htmlTextBox" type="text" runat="server"> Then call the following method from the Page_Load in the code behind file. Notice that this works for WebControls and HtmlControls. Example: How to use the SetInitialFocus method public void TestSetInitialFocus() { //Snippets00004.SetInitialFocus(TextBox1); Snippets00004.SetInitialFocus(htmlTextBox); } If you load the test aspx page in your browser, you should see that the selected control has the cursor focus. Here's the class: The SetInitialFocus method embedded in a class. namespace Cambia.CoreLib { using System; using System.Text; using System.Web.UI; using System.Web.UI.WebControls; /// <summary> /// Useful C# snippets from CambiaResearch.com /// </summary> public class Snippets00004 { public Snippets00004() { } public static void SetInitialFocus(Control control) { if (control.Page.IsClientScriptBlockRegistered("InitialFocus")) return; if (control.Page == null) { throw new ArgumentException( "The Control must be added to a Page before " + "you can set the IntialFocus to it."); } if (control.Page.Request.Browser.JavaScript == true) { // Create JavaScript StringBuilder s = new StringBuilder(); s.Append("\n<SCRIPT LANGUAGE='JavaScript'>\n"); s.Append("<!--\n"); s.Append("function SetInitialFocus()\n"); s.Append("{\n"); s.Append(" document."); // Find the Form Control p = control.Parent; while (!(p is System.Web.UI.HtmlControls.HtmlForm)) p = p.Parent; s.Append(p.ClientID); s.Append("['"); s.Append(control.UniqueID); // Set Focus on the selected item of a RadioButtonList RadioButtonList rbl = control as RadioButtonList; if (rbl != null) { string suffix = "_0"; int t = 0; foreach (ListItem li in rbl.Items) { if (li.Selected) { suffix = "_" + t.ToString(); break; } t++; } s.Append(suffix); } // Set Focus on the first item of a CheckBoxList if (control is CheckBoxList) { s.Append("_0"); } s.Append("'].focus();\n"); s.Append("}\n"); if (control.Page.SmartNavigation) s.Append("window.setTimeout(SetInitialFocus, 500);\n"); else s.Append("window.onload = SetInitialFocus;\n"); s.Append("// -->\n"); s.Append("</SCRIPT>"); // Register Client Script if (!control.Page.IsClientScriptBlockRegistered("InitialFocus")) control.Page.RegisterClientScriptBlock("InitialFocus", s.ToString()); } } } }