string was not recognized as a valid datetime in Asp.Net

DateTime.ParseExact which parses a date that exactly matches a format you supply.

string date1 = "12/29/2011";

        DateTime date2 = DateTime.ParseExact(date1, "MM/dd/yyyy", null);

null means the current culture.

 OR

using System.Globalization;

date2 = DateTime.ParseExact(date1, "MM/dd/yyyy HH:mm:ss", CultureInfo.InvariantCulture);

Email Binding in Asp.Net GridView

<asp:TemplateField HeaderText="Email">

                        <ItemTemplate>

                            <asp:HyperLink runat="server" ID="HyperLink1" NavigateUrl='<%# string.Format("mailto:{0}", Eval("Email")) %>'

                                Text='<%# Eval("Email") %>' />

                        </ItemTemplate>

                        

                    </asp:TemplateField>

Maxlength of Multilne Textbox in ASP.Net

<script language="javascript" type="text/javascript">

function textboxMultilineMaxNumber(txt, maxLen)

{

    try {

        if ((txt.value.length) > (maxLen-1 ))

        return false;

        }

 catch (e)

    {

    }

}

    </script>

<asp:TextBox ID="TextBox1" runat="server" Width="200px" TextMode="MultiLine" Height="100px"  onkeypress="return textboxMultilineMaxNumber(this,5)"></asp:TextBox>

Disable Cut, Copy & Paste in ASP.Net textbox

  <asp:TextBox ID="TextBox1" runat="server" oncopy="return false" onpaste="return false"

            oncut="return false"></asp:TextBox>

Generate random file names in Asp.net

//Random FileName with Random Extension

        string fileName = System.IO.Path.GetRandomFileName();

        //Random FileName without Random Extension

        string fileNameWithoutExtension = System.IO.Path.GetFileNameWithoutExtension(System.IO.Path.GetRandomFileName());

Browser Detection in ASP.NET

System.Web.HttpBrowserCapabilities browser = Request.Browser;

                    string name = browser.Browser;

                    float version = (float)(browser.MajorVersion + browser.MinorVersion);

                    if ((name == "IE" && version == 6))

                    {

                     

                    }