How to display message box after saving data in ASP.Net

i want to show msg alert when record is inserted..when record is not inseted it show alert not inserted. how we can perform ..

<asp:Content ID="Content2" ContentPlaceHolderID="ContentPlaceHolder1" Runat="Server">
    <script type="text/javascript">
            function aa() {
                alert("record insert!");
            }</script>
    <br />
    <br />
    <table align="center" class="style1" bgcolor="#FFFFCC">
    <tr>
        <td class="style2" align="left">
            Serial NO</td>
        <td align="left">
            <asp:Label ID="Label1" runat="server"></asp:Label>
        </td>
    </tr>
    <tr>
        <td class="style9" align="left">
            New Item</td>
        <td align="left" class="style6">
            <asp:TextBox ID="TextBox2" runat="server" ontextchanged="TextBox2_TextChanged"></asp:TextBox>
        </td>
    </tr>
    <tr>
        <td class="style7" align="left">
            New Item (HIndi)</td>
        <td align="left" class="style8">
            <asp:TextBox ID="TextBox3" runat="server" Font-Names="Kruti Dev 010" 
                Width="128px"></asp:TextBox>
        </td>
    </tr>
    <tr>
        <td class="style3" align="left">
            Service Tax</td>
        <td align="left" class="clear">
            <asp:RadioButtonList ID="RadioButtonList2" runat="server" Width="61px">
                <asp:ListItem Selected="True">0</asp:ListItem>
                <asp:ListItem>6</asp:ListItem>
                <asp:ListItem>8</asp:ListItem>
            </asp:RadioButtonList>
        </td>
    </tr>
    <tr>
        <td class="style5" align="left">
            &nbsp;</td>
        <td class="style6" align="left">
                &nbsp;&nbsp;
                <asp:Button ID="Button4" runat="server" Text="save" onclick="Button4_Click"  OnClientClick=" javascript:aa()" 

                    Width="85px" style="height: 26px" />
                &nbsp;&nbsp;&nbsp;&nbsp;
                <asp:Button ID="Button5" runat="server" Text="edit" onclick="Button5_Click"  Width="85px" />
            </td>
    </tr>
    <tr>
        <td class="style5">
            &nbsp;</td>
        <td class="style6">
            <asp:Literal ID="Literal1" runat="server"></asp:Literal>
            </td>
    </tr>
</table>
                
                
            </asp:Content>