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<H1><A NAME="SECTION006000000000000000000">
4. Creating a first dynamic website: Hello, you !</A>
</H1>
<P>
Edit the file <span class="file">Hello.cpy</span> that we've created in the previous chapter, and change it to:
<P>
<div class="verbatim"><pre>
CherryClass Root:
mask:
def index(self, name="you"):
<html><body>
Hello, <b py-eval="name"></b> !
<form py-attr="request.base" action="" method="get">
Enter your name: <input name=name type=text><br>
<input type=submit value=OK>
</form>
</body></html>
</pre></div>
<P>
Recompile the file and restart the server. Now, refresh the page in your browser. You should see
<div class="verbatim"><pre>
Hello, you
</pre></div>
<P>
followed by a field where you can enter
some text. Enter your name and press the OK button. Now the string has changed to
<P>
<div class="verbatim"><pre>
Hello, "your name"
</pre></div>
<P>
How does it work ?
<P>
This time, the <var>index</var> method has a parameter called <var>name</var>. Just like for any Python method, this
parameter can have a default value (in this case, <var>you</var>). The first time the browser displays the page,
it doesn't pass any <var>name</var> parameter, so <var>name</var> will have its default value in the function.
<P>
When you fill out the text field and hit OK, the browser will request the same page, but this time, <var>name</var> will be
passed as a parameter and it will contain the name you entered.
<P>
Because we used <var>method="get"</var> in the form, the name parameter will be passed using the URL (you can check that the
URL in your browser looks like: <a class="url" href="http://localhost:8000/?name=yourName">http://localhost:8000/?name=yourName</a>).
<P>
Now, edit <span class="file">Hello.cpy</span> and change <var>method="get"</var> to <var>method="post"</var>. Recompile the file, restart
the server and redo the test: it works exactly the same way, except that <var>name=yourName</var> doesn't show up in the URL.
This is because we used a <var>POST</var> method instead of a <var>GET</var> method for the form.
<P>
What we've learned:
<UL>
<LI>Parameters sent by the browser using the URL (GET) or using a POST are passed to the method via regular Python parameters.
It doesn't matter if it's a GET or a POST, or if the parameter is a short string or a large file. It will always be
handled the same way
</LI>
<LI>In a mask method, you can use special tags like <code>py-eval</code> or <code>py-attr</code>. Those tags are part or the CherryPy
templating languages.
</LI>
</UL>
<P>
It's now time to do more intersting things with the templating languages...
<P>
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<span class="release-info">Release 0.10, documentation updated on 19 March 2004.</span>
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