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We just added an action method to process
form post for the Entries/Add path.

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00:00:06,480 --> 00:00:09,980
Now we're ready to capture
the request post data.

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00:00:09,980 --> 00:00:14,169
Make sure that you've got a breakpoint
in the AddPost action method like you

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see here.

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00:00:14,762 --> 00:00:17,827
Press F5 to start the app.

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00:00:17,827 --> 00:00:20,173
Then browse to the Add Entry page.

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00:00:22,415 --> 00:00:29,530
Enter 1/1/2016 for the date field
value and click the Save button.

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00:00:31,270 --> 00:00:33,030
And now we're at our breakpoint.

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Let's see if we can find the request
form data in the Autos window.

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00:00:37,705 --> 00:00:40,200
I'll make the window a little larger.

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00:00:42,880 --> 00:00:46,880
If we expand this, and Request,

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00:00:49,390 --> 00:00:53,130
we can see that it has
a property named Form.

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00:00:53,130 --> 00:00:56,650
And to the right in the value column,
we can see our form data.

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00:00:57,930 --> 00:01:00,060
Let's go ahead and stop the app.

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00:01:00,060 --> 00:01:04,823
The Request Form property can be used
to extract our form values like this.

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00:01:04,823 --> 00:01:10,402
string date = Request.Form,

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00:01:10,402 --> 00:01:17,640
a pair of brackets, and the string Date.

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00:01:18,650 --> 00:01:22,904
This approach is similar to how we index
into an array to get a reference to

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00:01:22,904 --> 00:01:24,176
a specific element.

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00:01:24,176 --> 00:01:28,977
But instead of using a number for
the index, we use a string that

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00:01:28,977 --> 00:01:34,200
matches the form field name we
want to retrieve the value for.

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00:01:34,200 --> 00:01:39,189
This line of code just extracts
the date form field value.

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00:01:39,189 --> 00:01:43,062
We'd need to repeat this line of code for
each form field..

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00:01:45,922 --> 00:01:52,852
ActivityId, Duration,

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00:01:52,852 --> 00:02:01,680
Intensity, Exclude and Notes.

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00:02:01,680 --> 00:02:06,740
Repeating this line of code for
each form field would get ugly real fast.

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00:02:06,740 --> 00:02:11,920
Luckily, MVC provides us with a much
better way of capturing our form data.

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We can simply define method parameters for
each form field value we need to capture.

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00:02:18,080 --> 00:02:21,110
string date, for the date field.

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00:02:22,580 --> 00:02:27,440
string activityId, for the activity field.

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00:02:28,820 --> 00:02:31,470
string duration, for the duration field.

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00:02:33,900 --> 00:02:36,790
string intensity, for the intensity field.

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00:02:38,250 --> 00:02:41,740
string exclude, for the exclude field.

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00:02:41,740 --> 00:02:45,830
And lastly, string notes,
for the notes field.

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00:02:45,830 --> 00:02:48,980
Also, now that we've added
parameters to our method, we

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00:02:48,980 --> 00:02:53,817
can change the name of the method back to
Add, and remove the ActionName attribute.

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This is possible because
our method signature

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now differs from the other Add method.

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00:03:01,240 --> 00:03:03,797
Let's run our app again and
see how this works.

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00:03:06,143 --> 00:03:10,570
I'll enter the values 1/1/2016,

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00:03:10,570 --> 00:03:15,115
1 for Activity, 23 for Duration, Low for

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Intensity, and
leave Exclude and Notes blank.

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00:03:20,750 --> 00:03:22,890
Then click the Save
button to post the form.

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00:03:25,308 --> 00:03:28,590
Okay, here we are at our breakpoint again.

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00:03:28,590 --> 00:03:34,880
In the Autos window, we can see that
the date, activity, duration and

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00:03:34,880 --> 00:03:39,390
intensity parameters all contain
the values that we provided in the form.

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00:03:39,390 --> 00:03:41,080
How does this work?

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00:03:41,080 --> 00:03:45,280
At a high level, when MVC has rendered
a request to an action method,

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00:03:45,280 --> 00:03:47,260
it looks at that method's parameters.

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And attempts to set their values by
looking for request form fields,

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route data or request query string
parameters with the same names.

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00:03:56,140 --> 00:04:01,750
This process, which is an important
part of MVC is called model binding.

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00:04:01,750 --> 00:04:03,920
The part of MVC that's responsible for

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00:04:03,920 --> 00:04:07,470
model binding is known
as the model binder.

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00:04:07,470 --> 00:04:10,780
If you'd like to learn more
about how model binding works,

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see the teacher's notes for
links to additional resources.

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Go ahead and press F5 to continue.

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Notice that when the form is re-displayed,
we're losing our values that we provided.

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Why is this a problem?

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00:04:23,710 --> 00:04:28,540
Well, sometimes it's necessary to
re-display the form back to the user.

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00:04:28,540 --> 00:04:32,970
For instance, if the user doesn't
supply all the required values,

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00:04:32,970 --> 00:04:36,190
we'd want to re-display
the form along with a message

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asking the user to provide
the missing values.

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00:04:39,410 --> 00:04:41,395
This is called form validation.

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00:04:41,395 --> 00:04:45,400
We'll see how to implement form
validation later in this course.

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For now, let's use ViewBag to flow our
parameter values back to our form.

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ViewBag.Date = date.

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00:05:03,891 --> 00:05:11,289
ViewBag.ActivityId = activityId.

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ViewBag.Duration = duration.

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00:05:17,887 --> 00:05:24,583
ViewBag.Intensity = intensity.

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00:05:24,583 --> 00:05:31,686
ViewBag.Exclude = exclude.

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ViewBag.Notes = notes.

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00:05:39,070 --> 00:05:43,451
Then, in our View, we need to set
the input element value attributes to

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the corresponding ViewBag property values.

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00:05:46,348 --> 00:05:55,000
value= @ViewBag.Date.

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00:06:01,748 --> 00:06:07,961
Value= @ViewBag.ActivityId.

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Value= @ViewBag.Duration.

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Value= @ViewBag.Intensity.

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Value= @ViewBag.Exclude.

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00:06:47,431 --> 00:06:50,330
And then, for the text area element,

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Just set its inner content to
the ViewBag Notes property value.

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00:07:07,599 --> 00:07:09,040
Let's test our app again.

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This time, let's provide a value for

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00:07:14,058 --> 00:07:18,606
every field to ensure that
they all persist correctly.

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00:07:18,606 --> 00:07:22,797
Date, Activity, Duration,

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00:07:22,797 --> 00:07:28,283
Intensity, Exclude, and then Notes.

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00:07:31,322 --> 00:07:32,662
Then click Save.

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Here's our breakpoint again.

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00:07:42,380 --> 00:07:46,961
Press F5 to continue, and
here's all of our values.

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Go ahead and stop the app.

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00:07:52,130 --> 00:07:54,770
If you're using GitHub,
let's commit our changes.

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Enter a commit message of Updated the Add

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00:08:00,654 --> 00:08:05,025
action method to capture POST data,

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00:08:05,025 --> 00:08:08,980
and click the Commit All button.

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As we were fixing the flow
of values to our form,

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00:08:14,710 --> 00:08:18,970
you were probably getting the feeling
there's a better way to do this.

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00:08:18,970 --> 00:08:21,380
And, you're right, of course.

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00:08:21,380 --> 00:08:24,040
But don't worry,
by the end of this section,

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00:08:24,040 --> 00:08:26,930
we'll have all of
the necessary pieces in place.

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00:08:26,930 --> 00:08:30,250
So we don't have to do
these kinds of workarounds.

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00:08:30,250 --> 00:08:33,940
In the next video, we'll continue
to improve our Add action method.