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And actually we're going to start

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on this add a new user page here, this page.

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There I get a very simple form,

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it's this new user EJS file which is responsible for it.

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And there I got one input where I want a username,

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so some simple text input.

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And then I got this part here, where I want a user image,

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and I got these question marks here

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to signal that I will need to add something there,

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because at the moment we've got no way of picking an image,

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we can just click this button, but of course right now,

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we're not yet ready to submit this form.

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So how can we now ensure that a user

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is able to select an image?

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Well, thankfully that's a core functionality,

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you are not the first one

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who wants to add such a feature to a website.

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And therefore, thankfully, there is an HTML element

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that allows us to add a file picker.

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And that indeed actually is the input element again,

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which we already used up here,

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and which we saw a lot throughout the course already.

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But here we now don't want type text,

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but instead there is type file, which you can set.

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That's one of the built in types,

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which is supported by all browsers,

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and this will do what the name suggests.

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It will in the end give us an input

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that allows us to select a file.

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Now we can give this an ID, image and a name,

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like, image again.

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And if we now save that and we then reload this form,

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we got this file picker here,

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which gives us this choose file button here, this option.

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Now we can click this button,

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and it will open this file picker for us here,

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and you can then navigate around on your system

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to select the folder where the file lives,

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that you wanna upload.

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And here I prepared a simple file, an image of myself here,

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and you can of course, try this with any image.

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It should be an image here

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to proceed with the rest of this section,

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because I will later also show you

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how to preview this image, but theoretically of course,

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you could pick any file.

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But here I'm going to go with an image and I can click open.

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Now we don't see a preview here.

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We don't see a preview of the image,

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that is something we would have to build on our own.

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And it is something we will build on our own

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throughout this section, but to get started,

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to keep things simple right now,

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we will just leave it like this.

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And now we've got this file added here,

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now we could enter a username as well,

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and then submit this form.

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But, before we do that there are a couple of other things

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we might wanna do, and at least one other thing

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we have to do.

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Now let's start with the things we might wanna do.

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Besides showing a preview,

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which is something we'll explore later,

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we of course might wanna configure this file input

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a little bit more,

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to control which kind of files are selected here.

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For example, we can again add required,

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to ensure that we must have some file.

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If I set required here and I reload this page,

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and I enter a username here, but then I don't choose a file,

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I get a warning here,

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so that might be something we might wanna do.

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In addition, it's very likely that we don't wanna accept

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all kinds of files, but that, for example here,

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we want an image.

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So therefore, thankfully with the file input,

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we can also restrict the types of files

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that can be selected here.

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For this, to achieve this,

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we can add an accept attribute here,

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and then there you can simply list the file extensions

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that you wanna allow, for example, .JPG.

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And then this is a comma separated list,

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you can add all the files you do want to allow,

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like also JPEG with an E.

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Now we can only select such files.

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And to prove this, if I temporarily set this to only PNG,

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and save that, and we then go back and reload.

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If I click choose file, I can't select this JPEG file here.

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So that's how you can control

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which files can be selected here.

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Now there are different ways of writing this.

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You can list those extensions,

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the dot is important in that case.

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You can also write something like image, slash JPEG,

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to allow all JPEG images,

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no matter if the file ends with JPEG with an E,

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or without an E.

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And you can then also still combine that like this,

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or you can type image, slash star to allow all images,

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but for example, no PDF documents.

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Here I will write image, slash JPEG,

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comma image, slash PNG, to allow JPEG and PNG files.

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With that if I reload, I can select my JPEG file here,

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and I can also select that if it ends with JPEG with an E.

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So now this can be selected,

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and we now do have that file in this form.

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Again, a preview might be nice to have,

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but that's a little bit more advanced,

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hence I'll dive into this later, and then for instead now,

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I wanna focus on submitting this form,

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on the client side for now.

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Handling it on the back end

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will be the next step thereafter.

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And that is the mandatory step, which is not optional.

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You might wanna control what gets selected here,

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you definitely have to control

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how this form is submitted, though.

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Right now it's configured as a default form,

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with some path and this method.

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Now this worked up to this point in the course,

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but as soon as your form includes files,

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you have to add an extra attribute to your form.

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And that's the enc type attribute.

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This controls how the form is encoded,

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so how that data, which is part of this page,

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will be packed into the request body by the browser,

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when the browser sends that request,

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with that data to the server.

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So the browser will do the heavy lifting,

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but you have to tell the browser how it should be done.

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Now the default mode is, application/x-www-form-urlencoded,

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which sounds super weird and fancy,

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but that's just a default way of submitting forms,

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which we automatically used thus far.

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Since it's the default, we didn't have to specify it.

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But now we wanna use multipart/form-data.

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That's the encoding type you have to choose,

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if you have a form that includes at least one file picker.

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If you have no file picker, you could also use it,

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but then the other mode, the default mode is recommended.

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But if you have at least one file,

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you must switch to enc type, multi-part form data,

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for that file to be submitted to the server successfully.

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And therefore that was a mandatory step.

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With that, if we now save this,

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we would be able to submit this form,

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as soon as we also enter a username.

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But before we can do that,

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we now of course have to move to the server side,

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to the backend, and write some code there

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to handle this incoming request,

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and most importantly, to also handle the incoming file.