Display NULL in ASP.Net GridView when default date is 1900-01-01 using C# and VB.Net

Hey haider6.9,

Please refer below sample.

HTML

<asp:GridView runat="server" AutoGenerateColumns="False" DataSourceID="SqlDataSource1"
    OnRowDataBound="OnRowDataBound">
    <Columns>
        <asp:BoundField DataField="ID" HeaderText="ID" InsertVisible="False" ReadOnly="True"
            SortExpression="ID" />
        <asp:BoundField DataField="Birth" HeaderText="Birth" DataFormatString="{0:dd/MM/yyyy}" SortExpression="Birth" />
    </Columns>
</asp:GridView>
<asp:SqlDataSource ID="SqlDataSource1" runat="server" ConnectionString="<%$ ConnectionStrings:ConnectionString %>"
    SelectCommand="SELECT * FROM [Test]"></asp:SqlDataSource>

Code

C#

protected void OnRowDataBound(object sender, GridViewRowEventArgs e)
{
    if (e.Row.RowType == DataControlRowType.DataRow)
    {
        DateTime birthDate = Convert.ToDateTime(e.Row.Cells[1].Text);
        if (birthDate.ToShortDateString() == "1/1/1900")
        {
            e.Row.Cells[1].Text = "null";
        }
    }
}

VB.Net

Protected Sub OnRowDataBound(ByVal sender As Object, ByVal e As GridViewRowEventArgs)
    If e.Row.RowType = DataControlRowType.DataRow Then
        Dim birthDate As DateTime = Convert.ToDateTime(e.Row.Cells(1).Text)

        If birthDate.ToShortDateString() = "1/1/1900" Then
            e.Row.Cells(1).Text = "null"
        End If
    End If
End Sub

Screenshot