how to write a Confirmation message using javascript

We use the confirm function to get the confirmation from the user.

Note : to prevent postback of a button click based on the confirmation by the user, you need to return true/ false from the calling function and from the calling event.

( OnClientClick="return getConfirm();" )



Code Sample :


Design <script language="javascript">
        function getConfirm
        {
                return confirm("Are you sure want to get the server time?");
        }
</script>

Page loaded at
Server Time : <asp:Label ID="lblTime" runat="server"></asp:Label> <br />
<br /> <asp:Button ID="btnGetServerTime" runat="server" Text="Get Server Time" OnClientClick="return getConfirm();"
OnClick="btnGetServerTime_Click" />
 
.CS Page protected void Page_Load(object sender, EventArgs e)
{
        if(!IsPostBack)
                lblTime.Text = DateTime.Now.ToString();
}
protected void btnGetServerTime_Click(object sender, EventArgs e)
{
        lblTime.Text = DateTime.Now.ToString();
}


O/p:

Once you click on the button it will ask yes/ no option. if you press yes option will execute the post back event of the button . if you press no button nothing will performed

Page loaded at
Server Time : 7/8/2014 3:55:48 AM