php 'if' and emails | Still Plugging Away

Here we explore a bit more about the php programming language. Topics include:

Logical / boolean 'true' and 'false'
Comparison operators
The 'if' statement
$_GET, $_POST, and $_SERVER arrays
How to send emails from a php CGI: the mail() function

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Lesson 07, part 1
More php: comparisons, 'if', and emails

Click here for the video transcript

Hands on exercise

This exercise is focused on coding 'if' statements, sending emails, and accessing the $_SERVER variables.

This exercise builds on your previous cgi, Feedback.php

In your Feedback.php code, extend the code to accomplish the following:
Add variable declarations to support emails:
- $mailto: set to be your email address
- $headers: set to have a "From:" header
- $subject should be "Server variable values"
- $msg should contain "For this request, we find the following server values: \n \n";
Add variable declarations to capture the server variables discussed in the lecture; maybe:
- $serverAddr to hold $_SERVER["SERVER_ADDR"]
- $serverName to hold $_SERVER["SERVER_NAME"]
- $requestMethod to hold $_SERVER["REQUEST_METHOD"]
- $queryString to hold $_SERVER["QUERY_STRING"]
- $referer to hold $_SERVER["HTTP_REFERER"]
- $remoteAddr to hold $_SERVER["REMOTE_ADDR"]
- $remoteUser to hold $_SERVER["REMOTE_USER"]
After the 'echo' of the $suggestion variable, add 'echo' statements to display membership status and resident status, if they have values
Then echo a <ul> start tag
Then for each of the seven $_SERVER variables mentioned in the lecture:
- If the variable has a value:
 - concatenate the variable value to the $msg string, maybe like:
 "variable_name is variable_value"
 - echo an <li> element: containing "variable_name: variable_value"
echo a </ul> end tag
echo 'body' and 'html' end tags, then if an email address has been supplied, invoke the 'mail()' function to send an email
Test your CGI works by getting to SuggestionBox.shtml and trying various values. Make sure you receive the email sent from the CGI.

Session 2
Complex 'if' statements

Here we explore logical operators and nested 'if' statements:

Logical operators (and, or, xor, !)
Nested 'if's

Lesson 07, part 2
Logical operators

Click here for the video transcript.

Hands on exercise

This exercise is primarily focused on setting up a new CGI that will implement nested 'if' statements in the next exercise.

The Table 'N' Fable club has organized a trip to visit locations in Wales named in the mystery novel "Welsh Rarebit Gone".

In lesson 4's lab, you constructed the HTML page 'signUp.shtml', which includes a form that invokes a CGI named 'AddTraveler.php' in your 'cgis' directory.

So in this exercise you will code cgis/AddTraveler.php - a new CGI

Here are steps to construct your first cut at AddTraveler.php:

Open phpStarter.txt and save it as 'AddTraveler.php' in your AdvancedWebFiles/cgis directory and then:
- replace "==purpose / goal of cgi" with "cgi to process a sign up for our trip to Wales"
- replace "==how invoked (method, webpage)" with "invoked using POST from signUp.shtml"
- add some comments regarding the goals of the CGI, such as:
 - Build user street address, two parts (you'll not write the code until the next exercise)
 - Build a response page, including the constructed street address
 - Send an email alerting you to the new sign up
- under the comment "get variables from form "
 - retrieve all the variables from the form into php variables
 Important point: since this form includes a file upload (possible picture of applicant), all variables must be accessed using $_POST, except the file, which is accessed using $_FILES
 - so use $_POST["name"]
 Example: $first = $_POST["firstname"]; and
 $last = $_POST["familyname"];, etc.
 - except use $_FILES["pic"] for the file item with name 'pic'
- under the comment "variables used in our work"
 - declare the following variables:
 - $mailto = - put your personal name and email there
 - $subject = "A new sign up for the Wales trip!"
 - $headers = "From: put your email address here"
 - $msg = "$first $last has signed up to join our trip to Wales.\n";
- below the comment "/* build response page */", build the response page for the user:
 - use the 'echo' statements already there for 'doctype', 'html' start tag, and 'head' start tag then add the following:
 - echo a <title> element with value "Sign-up results"
 - echo </head>, an end head element tag
 - echo <body>, a body element start tag
 - echo an <h1> element with content
 "Welcome $first, thanks for signing up to join our trip to Wales!"
 - echo a element with:
 "One of the trip leaders will contact you soon to answer questions"
 - echo </body>, a body end tag
 - echo </html>, an html end tag
- after the echo of </html>, send your email message to yourself
- Save the resulting AddTraveler.php file and upload it to your AdvancedWebFiles/cgis directory

Test your sign up form / cgi combination: verify you get the email as expected and the user sees the feedback page.

Session 3
Addresses

Here we explore displaying addresses on a website, along with another opportunity to use nested if's.

Display vs. security
How to format / display addresses

Lesson 07, part 3
Addresses

Click here for the video transcript.

Hands on exercise

This exercise is primarily focused using complex 'if' statements to construct a correctly formatted street address, based on what data the user has supplied. It modifies your new AddTraveler.php code.

In this exercise you will extend cgis/AddTraveler.php - your new CGI

Here are steps to update AddTraveler.php:

under the comment "variables used in our work" add the following variable declares:
- $addr = "" - used for holding the street address we build
- $addr_back = "" - to hold city, state, zip, country: the back end of the address
after the gathering of variables from the form, we're going to build / format the address as in the lecture, so
- add a comment: "/* construct front / top end of address */"
- the 'front end' is basically the street address, and we'll construct it in the variable "$addr":
 - if addr1 from the form is omitted, then $addr = "" and ignore $addr2
 - otherwise, $addr = address line 1 from the form
 - and if there is a value in address line 2 from the form then
 $addr = first_line second_line
- then add a comment "/* construct back / bottom end of address */"
- to build the back end of the address, we consider if there are values for city, state, mailcode and country:
 - if city and state have values: $addr_back = "$city, $state $zip";
 - if city has a value but state does not, then $addr_back = $city;
 - if city does not have a value but state does, then $addr_back = $state;
 - if country has a value and it's not "USA": $addr_back = $addr_back." ".$country;
- Finally, if both $addr and $addr_back are empty, set $addr to "N/A"
after the echo of the </head> end tag,
- after the text "One of the trip leaders will contact you soon to answer questions, " add
 echo: " and confirm the details as we have them."
- echo a element with
 "Here is the address we have for you: "
- echo "$addr $addr_back"

Save your updated AddTraveler.php and test it out, especially the formatting of addresses.

Lesson 7: php programming, 2