Pass arguments to dialog

[Thomas]

Hello,

i have a question regarding passing arguments to a dialog.
I have a grid with userdata implemented and don't want to use the custom edit function.
The reason is that In my database there are additional infos that don't need to be shown in the datatable, but should be editable in the dialog.

Extract of UserManagement.aspx:

function showEdit (e) {

            var wnd = $("#userEdit-form");

            initializeWindow(wnd, "Benutzer editieren", "600px");               

            wnd.data("kendoWindow").open();

        }

Extract of EditUser.ascx:

<li>

                <label for="firstName"><%=Labels.FirstName %>*</label>

                <input type="text" class="k-textbox" id="firstName" name="firstName" value="" required />

            </li>

How can I pass the selected user information to the value field of the dialog "EditUser"(In this case the firstname input field)?

Thank u in advance.