ScriptManager.RegisterStartupScript(this.UpdatePanel1, this.GetType(), "updateScript", "alert('Delete successfully!')", true);
If you do not need to use alert prompt information in updatepanel, you can use the following code:
this.Page.ClientScript.RegisterStartupScript(Page.GetType(), "PopWin", "<script language='javascript'>alert('Vote successful!');</script>", True)
This code cannot prevent refreshing, but it has a better user experience than directly writing Response.Write("<script>alert('Vote successful!');</script>")! When the prompt box pops up, the current page will not be blank!
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