OnClick event of button fires everytime on PageLoad

Question

I have a button below:

 <asp:Button ID="btnApprove" runat="server" Text="Approve" CssClass="button" OnClick="btnApprove_Click" />

Event handler of this button on server side is :

 protected void btnApprove_Click(object sender, EventArgs e)
    {
        Page.ClientScript.RegisterStartupScript(Page.GetType(), "key", "alert('Button Approve Clicked')", true);      
    }

Just get alert on the button click from the server side.

My issue is that once I clicked on Approve button, now when I load or refresh my page again this btnApprove_Click event gets executed everytime.

I have many others button on the same form but none shows this strange kind of behaviour. I tried to change this button as HTML but still the same behaviour.

Can anyone please help me to get out of it. Thanks in advance.

Answer 1

You should use IsPostBack on Page load to prevent every time page load on button click. You can check every time on Page_Load.

Sample Code

protected void Page_Load(object sender, EventArgs e)
{
    if (!IsPostBack)
    {
         // First Time Load When User Come 
    }
    else
    {
       // Every Time Load When Any click button in page
    }