Validation Controls

stu9820 · April 29th, 2004, 02:04 PM

I have validation controls and I'm wanting to create my own to make sure a checkbox is checked. Do I create a custom validator or use Javascript and if I use Javascript how do I go about making it validate along with the other validators?

melvik · May 1st, 2004, 02:13 AM

u can use RequiredFieldValidator or JavaScript to validate, but I guess u cant use RequiredFieldValidator for checkbox! (I couldnt)
I hope this samle will help u to validate checkbox in JavaScript :

Code:

<Script Runat="Server">
    private void Page_Load(object sender, System.EventArgs e)
    {
        Button1.Attributes["OnClick"]="return test();";
    }
</Script>
<html>
    <head>
        <script language="javascript">
            function test()
            {
                if( Form1.checkbox.checked )
                    return true;
                else
                    return false;
            }
        </script>
    </head>
    <body>
        <form id="Form1" method="post" runat="server">
            <INPUT id="checkbox" type="checkbox">
            <asp:Button id="Button1" runat="server" Text="Button"></asp:Button>
            <INPUT type="submit" value="Submit" onclick="return test();">
        </form>
    </body>
</html>

I use both HTML-Button & Web Control-Button for this samle. Page_Load is used bc I got error when I was trying for Web-Control button to validate.

HTH.

Always:),
Hovik Melkomian.

stu9820 · May 3rd, 2004, 07:46 AM

The problem is I have existing Validation controls and I'm trying to make sure the check box is checked. The question is how do I add code to make sure the checkbox is checked without breaking the Validations controls already on the page?

Is there a way to add Javascript like melvik shows with the Validation controls or do I have to create a Custom Validation control.

melvik · May 3rd, 2004, 09:03 AM

I guess u'd better to use Custom one, since u cant use requiredfieldvalidator & dont wanna use JavaScript.

Always:),
Hovik Melkomian.

stu9820 · May 3rd, 2004, 09:42 AM

Ahh... This is why your suggestion didn't work melvik.

"Using the CustomValidator server control in the way weâve just done integrates better with the life-cycle of your page. I openly recommend playing with various implementations of custom server-side validation routines, and the .NET Framework makes it very easy to roll your own. However, if youâre of the programming flow

That weâve populated our CheckBoxList control dynamically might make this tough for a client-side JavaScript routine, because weâd have to know ahead of time the specific values of the ID and Name attributes of the HTML Checkbox elements to access them, if we were to use the DHTML document object model (DOM), which would normally be the case. This is significantly easier using server-side logic. The .NET Framework automatically assigns each element in a WebForm a unique ID and/or Name, eliminating the chance for problems that would arise from clashes. However, this still doesnât make it any easier to program against them, not knowing what theyâll be at design-time.

Itâs not impossible â it would just take more work."

**I'm dynamically adding the checkboxs.

from - http://www.kuam.com/techtalk/customvalidatorclass.htm

stu9820 · May 3rd, 2004, 02:19 PM

Here is the solution:

<asp:checkbox id="isAgeOk" runat="server" text="I am over 18."></asp:checkbox>
<asp:customvalidator id="isAgeOkValidator" runat="server"
        errormessage="You must check the 'I am over 18.' checkbox."
        onservervalidate="isAgeOkValidator_ServerValidate"
        clientvalidationfunction="ValidateCheckbox" />

-------------------------

<script runat="server">

    Sub isAgeOkValidator_ServerValidate(ByVal source As Object, ByVal args As System.Web.UI.WebControls.ServerValidateEventArgs)
        args.IsValid = isAgeOk.Checked
    End Sub

</script>

<script language="javascript">

    function ValidateCheckbox(source, arguments)
    { arguments.IsValid = form1.isAgeOk.checked; }
</script>

Imar · May 3rd, 2004, 05:12 PM

Hi stu9820 (do you have another name as well??)

You can also take a look at Page.RegisterArrayDeclaration. This method allows you to create a client side array that is inserted at the end of the page. You could dump the ClientIDs of the controls you're interested in into this array, so you can iterate over this array from any JavaScript function to check their state, value etc.

I have used it in the past a couple of times for some complex client side validation, and it has served me well.

Cheers,

Imar

stu9820 · May 4th, 2004, 07:40 AM

Quote:

quote:Originally posted by Imar
(do you have another name as well??)

What do you mean?

Imar · May 4th, 2004, 07:47 AM

I was wondering if you had a "real name" as well. That is, I can't believe you were named stu9820 at birth.... ;)

Imar
---------------------------------------
Imar Spaanjaars
Everyone is unique, except for me.
While typing this post, I was listening to: Girl You Have No Faith In Medicine by The White Stripes (Track 13 from the album: Elephant) What's This?

stu9820 · May 4th, 2004, 08:32 AM

I am trying the Page.RegisterArrayDeclaration Method and I keep getting 'obj' is undefined.

My code:
HTML
<TABLE id="Table1" cellSpacing="0" cellPadding="0" border="0">
    <TR>
        <TD width="90">First Name:</TD>
        <TD>
        <asp:TextBox id="txtFirstName" runat="server"></asp:TextBox></TD>
    </TR>
    <TR>
        <TD>Last Name:</TD>
        <TD>
        <asp:TextBox id="txtLastName" runat="server"></asp:TextBox></TD>
    </TR>
    <TR>
        <TD>Email:</TD>
        <TD>
        <asp:TextBox id="txtEmail" runat="server"></asp:TextBox></TD>
    </TR>
    <TR>
        <TD>Phone:</TD>
        <TD>
        <asp:TextBox id="txtPhone" runat="server"></asp:TextBox></TD>
    </TR>
    <TR vAlign="top">
        <TD>Comments:</TD>
        <TD>
        <asp:TextBox id="txtComments" runat="server" Width="208px" Height="80px" TextMode="MultiLine"></asp:TextBox></TD>
    </TR>
    <TR>
        <TD></TD>
        <TD>
        <asp:Button id="Button1" runat="server" Text="Send"></asp:Button></TD>
    </TR>
</TABLE>

CODE BEHIND:
Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        Dim scriptString As String = "<script language=JavaScript> function doClick() {"
        scriptString += "for(var index=0;index < myArray.length;index++)"
        scriptString += " myArray[index].show(); } <"
        scriptString += "/" + "script>"

        RegisterStartupScript("arrayScript", scriptString)
        RegisterArrayDeclaration("myArray", "new obj('txtFirstName'),new obj('txtLastName'),new obj('txtEmail')")
    End Sub