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The most often used type of browser based persistence is through Forms. Forms allow you to share information from one page to the next. When used to construct a URL, you are able to persisting data over multiple users.
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The most often used type of browser
based persistence is through forms.
0:00
Forms allow you to share information
from one page to the next.
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They also allow you to capture user input
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that can then be utilized
by the application.
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This works great if we're going to use
the data to change the content of the next
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page, or to perform some action on
the server, such as sending an email.
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As an added benefit,
when using the get method on a form,
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the constructed URL allows you to
share those results with others,
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persisting data over multiple users.
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We'll be using forms in our
project to accept user input and
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also to tell our game which
word should be requested.
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I'll be using works spaces for
this project, but
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you’re always welcome to down load
the files and work on your own machine.
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Let's get started.
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We'll be starting a simple site that uses
the front in framework both strap for
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design.
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To learn more, so
the note associated with this video.
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This site has three pages, a welcome page,
a game page, and a story page.
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Let's take a look at what
we have in a browser.
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From our welcome page, if we click play,
we are taken to step one of five,
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where we're asked to enter our first word.
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Once we enter a word, And
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click submit,
we can see that the query string is added.
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But we're still on step one of five, and
we'll stay on step one of five forever,
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no matter how many times
we submit the form.
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Let's go back to work spaces and
update the code so
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that we can progress
through all five steps.
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Open play.php.
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At the top of the file,
you see a variable named page.
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This page variable is used to show our
step, and update the hidden form field.
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Once our page reaches a value greater than
the total, we redirect to the story page.
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The first thing we need to do is read the
data from the hidden field named p, and
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update our page variable.
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Always make sure that we
filter incoming data.
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Filter input, INPUT_GET,
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p, FILTER_SANITIZE NUMBER_INT,
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if the page variable is empty,
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Then we still want to
set the page equals one.
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Let's check these changes in the browser.
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This time, we can go through each step of
the forum until finally reaching the story
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at the end.
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Our placeholders are not being
filled in with the user data yet, so
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we still have some work to do, but
let's take a closer look at the form.
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We don't actually need to use
a form to submit a get request.
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We can just enter the query
string directly into the browser.
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We don't need to worry about
re-submitting a form and
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we can easily jump around to different
steps by changing our query string.
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If following a link can
add items to a cart,
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you might end up with products in your
cart that you never intended to purchase.
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In contrast, post can help prevent
users from doing things unintentionally
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by warning them when refreshing a page.
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Post is also more secure, especially
when combined with a secure certificate,
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because the values are not stored
directly in your browser history.
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You really don't want to be
putting passwords in a URL, right?
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One more thing to be aware of with
forms is that some browsers enforce
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a maximum path link of just
over 2,000 characters.
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This may seem like a lot, but
if you use the git method,
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it can be easier to reach that
limit than you may think.
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Long paths to files, long field names,
many field names, or
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even just accepting large
amounts of user input
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could mean that some of your
data is ignored without warning.
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The good news is that we can pass a URL
parameter along with a posted form.
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I want to be able to jump between steps
without actually submitting a form so
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that's the part that I want in the URL.
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Because our script is calculating
that value and it's not user input,
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we can actually add the query
string directly to our action.
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Now we can change the form method to post.
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The page value will be passed
in the query string, but
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the user entered data
will be passed via post.
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Great, we're ready to actually collect
the user input to write our story.
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One of the limitations with
forms is that by themselves,
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they only pass data over one request.
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If you want that data to be
available on another page,
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you would have to send that data through
another form or in the query string.
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For this project, we could continue to
AdWords as hidden values to the form, but
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then we would need to make sure that
we pose that data to the story page
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instead of redirecting
after handling the form.
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Instead, I'll show you how
sessions can be used to
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persist data throughout
a user's entire visit.
5:34
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