Validating form fields before printing with client side scripts

use two == instead of one

if (Page.IsValid == true)

I changed the = to have two as opposed to one, but still no luck. Here is what I have now:

OnClick="printButton_Click" OnClientClick="if (Page.IsValid == true) {window.print()}" />

It doesn't seem to be sending the e-mails anymore either since I made that change. For good measure, here is the code from the printButton_click event:

protected void printButton_Click(object sender, EventArgs e)
    {

        if (Page.IsValid)
        {
            string supplierName = supplierNameTextBox.Text;
            string returnAddress = returnAddressTextBox.Text;
            string pcName = pcNameTextBox.Text;
            string pcPhone = pcPhoneTextBox.Text;
            string pcFax = pcFaxTextBox.Text;
            string pcEmail = pcEmailTextBox.Text;
            string partNumber = partNumberTextBox.Text;
            string partDescription = partDescriptionTextBox.Text;
            string poNumber = poNumberTextBox.Text;
            string poLineNumber = poLineNumberTextBox.Text;
            string supplierNotificationDate = supplierNotificationTextBox.Text;
            string matReturnAuth = returnMatAuthTextBox.Text;
            string reasonReturned = reasonReturnTextBox.Text;
            string actionTaken = actionTakenTextBox.Text;
            bool correctiveActionRequired = correctiveActionRequiredCheckBox.Checked;
            string ncNumber = ncNumberTextBox.Text;
            string notes = notesTextBox.Text;
            string results = "Supplier Name:\t" + supplierName + "\n\nReturn Address:\t" + returnAddress + "\n\nPrimary Contact Name:\t" + pcName + "\n\nPrimary Contact Phone:\t" + pcPhone + "\n\nPrimary Contact Fax:\t" + pcFax + "\n\nPrimary Contact Email\t" + pcEmail + "\n\nPart Number:\t" + partNumber + "\n\nPart Desc:\t" + partDescription + "\n\nPO Number:\t" + poNumber + "\n\nPO Line Number:\t" + poLineNumber + "\n\nSupplier Notification Date:\t" + supplierNotificationDate + "\n\nMaterial Return Authorizatized By:\t" + matReturnAuth + "\n\nReason Returned:\t" + reasonReturned + "\n\nAction Taken:\t" + actionTaken + "\n\nCorrective Action Required?\t" + correctiveActionRequired + "\n\nNC Number:\t" + ncNumber + "\n\nNotes:\t" + notes;

            MailMessage message = new MailMessage();

            message.From = new MailAddress("WebForms@precision-aerospace.com");

            //message.ReplyTo = new MailAddress(senderEmail);

            message.To.Add(new MailAddress("rmarkley@precision-aerospace.com"));

            //message.To.Add(new MailAddress("kdorr@precision-aerospace.com"));

            //message.CC.Add(new MailAddress("rheyboer@precision-aerospace.com"));

            //message.CC.Add(new MailAddress("kwozniak@precision-aerospace.com"));

            //message.CC.Add(new MailAddress("dklompf@precision-aerospace.com"));

            //message.CC.Add(new MailAddress("jwaller@precision-aerospace.com"));

            //message.CC.Add(new MailAddress("jcase@precision-aerospace.com"));

            //message.CC.Add(new MailAddress("mkempf@precision-aerospace.com"));

            message.Subject = "Return Parts Notice";

            message.Body = results;

            SmtpClient client = new SmtpClient();

            client.Send(message);

            //Response.Redirect("confirmationPage.htm");
        }

    }
}

I have the e-mail portion of it working again. With this code

OnClientClick="if (Page.IsValid == true) {window.print()}" />

the web form posts back and emails the information, but does not launch the print dialog.

With this code:

OnClientClick="window.print()" />

The print dialog opens, but there is no validation so the user could basically print off a blank form if they wanted to. I want to prevent that by using the Page.IsValid. Is it possible to call that from a client side script and still open the print dialog with the same button. I realize that I could use two buttons, but the users around here get confused easily.

Thanks dakyd. That did exacly what I was looking for. I already had client side scripting enabled on my validation controls, but I never thought to group them. I had a felling that calling the Page class directly from the client side script wouldn't work out so well.

What do I do If the page has userControls and the User Controls have there own validators.
In addition ,the page also have a javascript validation which validates the required fields which gets called as from a customvalidatior in the page.

If I use this solution,wont the validations be happening twice?