Hi Waghmare,
I have created sample code which fullfill requirement.
HTML
<div>
    <asp:GridView ID="gvEmployees" runat="server" AutoGenerateColumns="false" OnRowDataBound="gvEmployees_RowDataBound">
        <Columns>
            <asp:BoundField DataField="EmployeeId" HeaderText="EmployeeId" />
            <asp:BoundField DataField="EmployeeName" HeaderText="EmployeeName" />
            <asp:TemplateField HeaderText="Pics">
                <ItemTemplate>
                    <asp:Image ID="empimage" Height="50px" runat="server" />
                </ItemTemplate>
            </asp:TemplateField>
        </Columns>
    </asp:GridView>
</div>
C#
protected void Page_Load(object sender, EventArgs e)
{
    if (!this.IsPostBack)
    {
        DataTable dt = new DataTable();
        dt.Columns.Add("EmployeeId", typeof(int));
        dt.Columns.Add("EmployeeName", typeof(string));
        dt.Rows.Add(1, "peter");
        dt.Rows.Add(2, "John");
        dt.Rows.Add(18, "Janet");
        dt.Rows.Add(101, "Margaret");
        dt.Rows.Add(1001, "Steven");
        dt.Rows.Add(10001, "Michael");
        gvEmployees.DataSource = dt;
        gvEmployees.DataBind();
    }
}
protected void gvEmployees_RowDataBound(object sender, GridViewRowEventArgs e)
{
    if (e.Row.RowType == DataControlRowType.DataRow)
    {
        string EmployeeId = e.Row.Cells[0].Text;
        (e.Row.FindControl("empimage") as Image).ImageUrl = "~/Files/" + "00000000".Substring(EmployeeId.Length, 8 - EmployeeId.Length) + EmployeeId + ".jpg";
    }
}
Screenshot

I hope works for you.