Get current login user id from Active Directory in ASP.Net using C# and VB.Net

Use

string name = new System.Security.Principal.WindowsPrincipal(System.Security.Principal.WindowsIdentity.GetCurrent()).Identity.Name;

 or

string name = System.Environment.UserName

 or

string name = Environment.GetEnvironmentVariable("USERNAME");

 or

string name = System.Security.Principal.WindowsIdentity.GetCurrent().Name;

Hi Amol111,

Refer below sample.

HTML

<asp:Button Text="Submit" runat="server" OnClick="OnSubmit" />

Code

C#

protected void OnSubmit(object sender, EventArgs e)
{
    string name = new System.Security.Principal.WindowsPrincipal(System.Security.Principal.WindowsIdentity.GetCurrent()).Identity.Name;
    ClientScript.RegisterStartupScript(this.GetType(), "alert", "alert('Logged in User\\n" + name + "');", true);
}

VB.Net

Protected Sub OnSubmit(ByVal sender As Object, ByVal e As EventArgs)
    Dim name As String = New System.Security.Principal.WindowsPrincipal(System.Security.Principal.WindowsIdentity.GetCurrent()).Identity.Name
    ClientScript.RegisterStartupScript(Me.GetType(), "alert", "alert('Logged in User\n" & name & "');", True)
End Sub

Screenshot