191. TD Submitting and Using the Form

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S… Speaker 1 (191. TD Submitting and Using the Form)

In the last lecture,

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we configured our form here.

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We added some controls by placing ng -model on the inputs.

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Now let's make this form submitable so that we can actually

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see what the user entered.

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S… Speaker 1 (191. TD Submitting and Using the Form)

For this...

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I'll go to my app component.

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I already do have a method here which we will use later.

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Let's ignore it for now.

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And I'll add a new method,

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onSubmit maybe.

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This should be triggered whenever this form is submitted by

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the user.

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In onSubmit,

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I want to output whatever the user entered.

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Well,

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first of all,

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we need to call this method.

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So back in the template,

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how can we call onSubmit?

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Now you might think that a good place would be on a click listener on this

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button here at the bottom,

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right? Because this is the button we click when we want to submit the form.

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However,

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this is not the best place to do it.

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Keep in mind that this button here is of type submit.

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So if we click it as it is placed inside of a HTML form

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element, something else will happen.

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The default behavior of HTML will be triggered

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here to call it like this.

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If you have a button in a form element,

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this button will submit the form,

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will send a request normally,

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but besides that,

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it will also trigger a JavaScript event,

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gsubmit event,

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that's built into JavaScript,

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built into HTML,

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you could say.

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S… Speaker 1 (191. TD Submitting and Using the Form)

Angular takes advantage of this and gives us

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a directive we can place on this form element as a whole.

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It is called ngsubmit

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and it actually only gives us one event we can listen to.

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So let's wrap it in parentheses.

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This event made available by the ngSubmit directive

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will be fired whenever this form is submitted.

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So whenever this default behavior is triggered.

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And here we can call onSubmit like

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this.

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And to show you that this works,

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I will simply go into onSubmit and log submitted

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here, just like that.

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Now if we save this and let it recompile let's go back and let's open up the developer

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tools

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And if I now hit the submit button,

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you see submitted here on the right because indeed the form

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gets submitted.

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Now it would be nice to see the actual values of

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the form though,

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to see that form object.

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And to see it,

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we have to go back to our template because we're in the template driven

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approach.

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So as a rule of thumb,

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everything you do,

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you do it in the template,

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everything.

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You want to change about this form,

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you want to add as functionality,

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you do it in a template.

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On this form object,

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we want to get access to the form created by Angular.

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Now you'll learn about local references you can place on HTML elements

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to get access to them.

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S… Speaker 1 (191. TD Submitting and Using the Form)

So we could place hashtag F on the form element,

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and now we could access this form element on,

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well,

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the F reference in our template,

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and we could pass F as an argument to the onSubmit method and

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print it there.

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So now we know that we get the form,

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and actually this will be of type element ref,

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as we learned.

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So if we import element ref and make this of type element ref here,

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and we output the form here,

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So this element.

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If we now go back to this and hit submit,

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yeah,

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we indeed see that form object.

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We see some strange classes here.

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I will come back to them.

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But that still is not what we want.

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It's not a JavaScript object created by Angular.

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But this object is there.

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We just need to know how to get to it.

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And there actually is a trick,

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you could call it.

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But it's no trick.

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It's the default way to get access to this automatically created object.

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You set this local reference equal to something.

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Now, we haven't done that yet.

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But we can set it equal to something.

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exposed by this form here.

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Keep in mind,

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the form element is kind of a selector for a directive

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built into Angular,

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which will create this JavaScript object automatically.

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And then it will expose some data we can fetch here on

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this form element.

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We can get access to it by writing ng form here between the

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quotation marks.

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So this might look super strange,

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but what this in the end does is it tells Angular,

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hey,

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please give me access to this form you created automatically.

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That's just something you have to keep in mind.

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This is how you get access to the form to this JavaScript object

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created by Angular automatically.

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So,

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therefore,

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here where we get this form,

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we now still pass it.

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Now this will no longer be an element ref,

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so let's remove this type here.

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Instead,

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this will now be of ngForm.

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So let's import ngForm from addAngularForms.

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And it kind of makes sense that it is of type ngForm,

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because that is what we're accessing here.

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This automatically created form.

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Now let's print it to the console one more time.

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And let's actually enter something into these fields to see

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that it worked.

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If I now type submit here,

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you see that now we get an ngForm object,

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an object which we certainly didn't create.

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And there we have a lot of properties.

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We'll have a closer look at those later.

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We also do have a value property.

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And if we expand this,

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we indeed see a couple of key value pairs here where

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we have the names of the controls.

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So the names we set up here on the name attribute

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like username and email.

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We find them here and then the values the user entered.

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And this is how we can submit such a form and how we can

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also get access to the form object created by Angular.

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S… Speaker 1 (191. TD Submitting and Using the Form)

We also see that our setup of controls also

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worked.

191. TD Submitting and Using the Form

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