o_19mgorv9t13a3ko71fev19l81mqa.pdf

Setting Ajax Options
I can fine-tune the behavior of the Ajax requests by setting values for the properties of the AjaxOptions object that I pass to
the Ajax.BeginForm helper method. In the following sections, I explain what each of these options does and why they can
be useful.
Ensuring Graceful Degradation
When I set up the Ajax-enabled form in Listing 23-10, I passed in the name of the action method that I wanted to be called
asynchronously. In the example, this was the GetPeopleData action, which generates a partial view containing a fragment
of HTML.
One problem with this approach is that it doesn’t work well if the user has disabled JavaScript (or is using a browser that
doesn’t support it). In such cases, when the user submits the form, the browser display discards the current HTML page and
replaces it with the fragment returned by the target action method. The effect can be seen in Figure 23-4.
Figure 23-4. The effect of using the Ajax.BeginForm helper without browser JavaScript support
Note I used Google Chrome for this figure because it makes it easy to toggle JavaScript.
The simplest way to address this problem is to use the AjaxOptions.Url property to specify the target URL for the
asynchronous request rather than specifying the action name as an argument to the Ajax.BeginForm method, as shown in
Listing 23-11.
Listing 23-11. Ensuring Gracefully Degrading Forms in the GetPeople.cshtml File
@using HelperMethods.Models
@model string
@{
ViewBag.Title = "GetPeople";
Layout = "/Views/Shared/_Layout.cshtml";
AjaxOptions ajaxOpts = new AjaxOptions {
UpdateTargetId = "tableBody",
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