The document provides an overview of how to build a basic web application. It explains that GET requests are used to retrieve data from a server and pass data in the URL, while POST requests are used to submit data without showing it in the URL, such as for passwords. It also introduces some key concepts for web applications, including using forms to collect user input, accessing submitted data with PHP (e.g. $_GET, $_POST), and storing data in databases with SQL queries (e.g. SELECT, INSERT).

1. How to build a web app
Or at least how to understand what a web app is better than you do now.
1

2. hey, it’s noah
2

3. 3

4. 4

5. My Story
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6. 6

7. 7

8. What is $44.6 billion?
8

9. 9

10. 10

11. Big Barrier #1
How do you pass stuff from one page to another?
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12. 12

13. It’s pretty much all forms
You hit a submit button and do something with a user’s data
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14. But how do you do it?
How do you take what someone types in and build something to respond to it?
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15. Let’s talk about HTTP
“HTTP functions as a request-response protocol in the client-server computing
model.”
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16. In english ...
HTTP is a set of nine things you can ask/tell a server.
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17. The Big Nine
1. HEAD
2. GET
3. POST
4. PUT
5. DELETE
6. TRACE
7. OPTIONS
8. CONNECT
9. PATCH
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18. The Big Nine Two
1. HEAD
2. GET
3. POST
4. PUT
5. DELETE
6. TRACE
7. OPTIONS
8. CONNECT
9. PATCH
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19. GET
For getting data (aka asking for something)
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20. POST
For posting data (aka submitting it)
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21. Simple enough, right?
But what does it really mean?
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25

26. search?q=passing+data
+from+one+page+to
+another
1. search
2. ?
3. q=
4. passing+data+from+one+page+to+another
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27. search?q=passing+data
+from+one+page+to
+another
1. search (page that is processing the data)
2. ? (start of query string)
3. q= (field name)
4. passing+data+from+one+page+to+another (query)
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28. When you type in any URL
Your browser is making a GET request.
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29. So the very easiest way to
pass data between pages
Is by putting it in the URL. You already do this, you just don’t realize it.
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30. 30

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32. 32

33. To get started making
simple web apps
All you need is two things ...
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34. 1. How to make a web form
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35. 2. How to do something with
the data in the URL on the
other end
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36. <form method=“get” action=“webapp.php”>
<input type=“text” name=“stuff”>
<input type=“submit”>
</form>
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37. Page that will
HTTP request method process our request
(passed in URL)
<form method=“get” action=“webapp.php”>
<input type=“text” name=“stuff”>
<input type=“submit”>
</form>
Name input will be
saved under
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38. Page that will
HTTP request method process our request
(passed in URL)
<form method=“get” action=“webapp.php”>
<input type=“text” name=“stuff”>
<input type=“submit”>
</form>
Name input will be
saved under
webapp.php?stuff=WHATEVERPEOPLETYPEIN
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39. 39

40. What will the URL be?
40

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ãóÑáêëíïÉÄ~ééLïÉÄ~ééKéÜé
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41

42. Now we just need to figure
out how to get stuff down
At this point we turn to our trusty language of choice.
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43. PHP
PHP Hypertext Protocol
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44. That’s right
It’s a RECURSIVE INITIALISM!
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45. Every language has its own
syntax for this stuff
We’re going to be using PHP because that’s what I know.
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46. So how do I get stuff down
from the URL in PHP?
It’s simple really.
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47. <? $_GET[‘stuff’];?>
That’s it. It’s all about what you do with it from there.
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48. <? print $_GET[‘stuff’];?>
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49. 49

50. <strong><? print $_GET
[‘stuff’];?></strong>
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51. 51

52. You wrote: <strong><?
print $_GET[‘stuff’];?></
strong>
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53. 53

54. We’ll dig in on more syntax
later ...
But you get the drift.
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55. POST
The other way to pass data.
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56. POST is generally used for
data you’re going to save.
But for now let’s just think of it as data you don’t want to show up in a URL.
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57. Like a password ...
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58. <form method=“post” action=“checkpassword.php”>
Password: <input type=“password” name=“password”>
<input type=“submit”>
</form>
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59. 59

60. <?
if($_POST['password'] == 'password1') {
print 'AWESOMECAKE!';
} else {
print 'FAIL!';
}
?>
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61. 61

62. <?
if($_POST['password'] == 'password1') {
print 'AWESOMECAKE!';
} else {?>
You got the password wrong, try again.<br />
<form method="post" action="checkpassword.php">
Password: <input type="password" name="password">
<input type="submit">
</form>
<?}
?>
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63. 63

64. That about covers barrier #1
Let’s do a quick recap
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65. Two main ways to pass data
between pages?
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66. GET & POST
66

67. Which one saves data in the
URL string?
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68. GET
68

69. Where does it put it?
69

70. URL: page.php?name=value
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71. Big Barrier #2
What the hell is a database?
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72. 72

73. 73
Column

74. Row
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75. Table
75

76. SELECT column_name
FROM table_name WHERE
column = value
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77. 77

78. SELECT * FROM sheet1
WHERE state = ‘CA’
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79. 79

80. INSERT into table_name
(column1,column2) VALUES
(value1,value2)
80

81. 81

82. INSERT INTO sheet1
VALUES (‘Noah Brier’, ‘1
Noah Street’, ‘NY’, ‘NY’,
‘10032’)
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83. 83

84. Let’s write some code
84

85. Download These
MAMP: http://www.mamp.info/en/downloads/index.html
TextWrangler: http://www.barebones.com/products/textwrangler/
download.html
Code: http://noahbrier.com/planningness.zip
OR YOU COULD GO TO http://noahbrier.com/planningness
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93. 93

94. The Basics
✤ $string = ‘string’;
✤ if($string == ‘string’) {print this;}
✤ else {print that;}
✤ $_GET[‘field_name’];
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