Updated 09SEP08: Now working in FF3, Jörn Zaefferer pointed out via the jQuery Mailing List that my script tag declaration was incorrect. I also added a better RegEx for the phone number.

I have been working on a proof of concept for a way to insert a bunch of contact data for a record. One of the requirements that has been pretty challenging is the client side validation since a lot of info isn't known until run time.

Demo (Tested in FF3, IE7, Chrome & Opera 9.5) | Download

1. User could enter anywhere from 1 to 5 contact methods in the case of this example.
2. If a type is entered then info is required and vice versa.
3. Depending upon the type chosen the validation is different.

So far I am using the jQuery Validation Plugin by Jörn Zaefferer which appears to have been around for quite a while with a big following.

Here is all of the jQuery:

        $(document).ready(function() {

            $("#myform").validate({
                //change the default placement of the error label
                errorPlacement: function(error, element) {
                    error.appendTo(element.parent("td").parent("tr").find(".errorTD"));
                }
            });

            //Add custom phone number validator - needs to be improved
            jQuery.validator.addMethod("phone", function(value, element) {
                return this.optional(element) || /^\d{3}-\d{3}-\d{4}$/.test(value);
            }
            , "* Please enter a phone number formated like XXX-XXX-XXXX");


            $(".wrapper").each(function() {
                var ddl = $(this).find(".type");
                var txt = $(this).find(".info");

                //Setup validation for dropdowns
                txt.blur(function() {
                    //remove any existing rules
                    ddl.rules("remove");

                    var tst = txt.val();

                    if (tst !== "") {
                        ddl.attr("title", "* Selection of a type is required.");
                        ddl.rules("add", {
                            required: true
                        });
                    }
                    else {
                        ddl.attr("title", "");
                    }


                });

                //Setup validation for text boxes
                ddl.blur(function() {
                    //remove and existing rules
                    txt.rules("remove");

                    var tst = ddl.val();
                    if (tst != "") {
                        txt.rules("add", {
                            required: function(element) {
                                return ddl.val() != "";
                            }
                        });

                        //If it is email add validation for email
                        if (ddl.val() == "3") {
                            txt.attr("title", "* Please enter a valid email address.")
                            txt.rules("add", {
                                email: true
                            });
                        }
                        else { //Has to be a phone number then
                            txt.attr("title", "* Please enter a phone number in XXX-XXX-XXXX format.")
                            txt.rules("add", {
                                phone: true
                            });
                        }
                    }
                });
            });
        });

And the HTML for the first Row:

    <tr class="wrapper">
        <td>1.</td>
        <td>
            <asp:DropDownList ID="DropDownListType1" runat="server" CssClass="type">
                <asp:ListItem Text="" Value=""></asp:ListItem>
                <asp:ListItem Text="Office Phone" Value="1"></asp:ListItem>
                <asp:ListItem Text="Mobile Phone" Value="2"></asp:ListItem>
                <asp:ListItem Text="Email" Value="3"></asp:ListItem>
                <asp:ListItem Text="Fax" Value="4"></asp:ListItem>
            </asp:DropDownList>           
        </td>
        <td>
            <asp:TextBox ID="TextBoxInfo1" runat="server" CssClass="info"></asp:TextBox>
        </td>
        <td class="errorTD">
            &nbsp;
        </td>
    </tr>

So I think I have a good start, but it could be improved still. Let me know what you think and what I missed.