如何使用javascript和asp.net放置警报框？

Question

I just want to know how to put an alert box using javascript and asp.net. Basically I have created a webpage where the admin will fill up a form, and then after clicking the submit button, there should be an alert box that will popup with a message that says upload successful or upload failed.

I tried doing it with this code(I only included the javascript code and the asp submit button):

<script>
    function UploadStatusSuccessful()
    {
        alert("Upload Successful!");
    }
</script>

<script>
    function UploadStatusFail()
    {
        alert("Upload Failed!");
    }
</script>

<asp:Button ID="Button1" runat="server" CssClass="submitButton" Text="Save 
Item" OnClick="Button1_Click"/>

and here is the code-behind:

protected void Button1_Click(object sender, EventArgs e)
{

    try
    {
        int item_brandId = 
        ConnectionClassBrands.GetIdByBrand(itemBrand.Text);
        string item_model = itemModel.Text;
        double item_price = Convert.ToDouble(itemPrice.Text);
        string item_image1 = Session["PicturePath1"].ToString();
        string item_image2 = Session["PicturePath2"].ToString();
        string item_description = itemDescription.Text;
        string item_necktype = itemNeckType.Text;
        string item_body = itemBody.Text;
        string item_fretboard = itemFretboard.Text;
        string item_fret = itemFret.Text;
        string item_bridge = itemBridge.Text;
        string item_neckpickup = itemNeckPickup.Text;
        string item_bridgepickup = itemBridgePickup.Text;
        string item_hardwarecolor = itemHardwareColor.Text;

        if (itemType1.Checked)
        {
            int item_type = 
            ConnectionClassBrands.GetIdByType(itemType1.Text);
            ItemType = item_type;
        }
        else if (itemType2.Checked)
        {
            int item_type = 
            ConnectionClassBrands.GetIdByType(itemType2.Text);
            ItemType = item_type;
        }

        var item = new instrumentItem
        {
            typeId = ItemType,
            brandId = item_brandId,
            model = item_model,
            price = item_price,
            itemimage1 = item_image1,
            itemimage2 = item_image2,
            description = item_description,
            necktype = item_necktype,
            body = item_body,
            fretboard = item_fretboard,
            fret = item_fret,
            bridge = item_bridge,
            neckpickup = item_neckpickup,
            bridgepickup = item_bridgepickup,
            hardwarecolor = item_hardwarecolor
        };

        ConnectionClassGuitarItems.AddStringInstrumentItems(item);

        Button1.Attributes.Add("onclick", "JavaScript:return 
        UploadStatusSuccessful()");

        ClearTextFields2();

    }
    catch (Exception)
    {
        Button1.Attributes.Add("onclick", "JavaScript:return 
        UploadStatusFail()");
    }


}

I tried doing the Button1.Attrbute.Add but no alert box is showing. Please provide solutions or actual examples on how to achieve this. Also kindly inform me if there are wrong syntax that i missed so that i can correct it immediately.

Answer 1

You can use ScriptManager.RegisterStartupScript in code behind to show alert message like below . You need to Scriptmanager control to your aspx page . This is the recommended way

 ScriptManager.RegisterStartupScript(this.Page, this.Page.GetType(), 
          "err_msg", 
          "alert('Upload failed!');",
          true);

Otherwise you can simple do like below

Response.Write("<script>alert('Upload failed!');</script>");

Link for scriptmanager control

http://msdn.microsoft.com/en-us/library/system.web.ui.clientscriptmanager.registerstartupscript.aspx

Answer 2

ScriptManager.RegisterStartupScript(this.Page, this.GetType(), "tmp", "<script type='text/javascript'>UploadStatusSuccessful();</script>", false);