instead of making disable i tried as making visible false for the button in gridview,like:
<asp:GridView runat="server" ID="GV1" AutoGenerateColumns="false">
<Columns>
<asp:BoundField DataField="Name" HeaderText="Name" />
<asp:BoundField DataField="Age" HeaderText="Age" />
<asp:TemplateField>
<ItemTemplate>
<asp:Button runat="server" Text="Reject"
Visible='<%# IsOverAgeLimit((Decimal)Eval("Age")) %>' />
</ItemTemplate>
</asp:TemplateField>
</Columns>
</asp:GridView>
Then, in the code behind, add in the method:
protected Boolean IsOverAgeLimit(Decimal Age) {
return Age > 35M;
}
check whether it is useful