CS457 Syllabus & Progress

Passing parameters to the web server: GET and POST methods

Executing PHP programs with parameters through a web-server

So far:
Example:

Webpages with parameters:

There are ways to "pass parameters" to webpages

Example:

Here's a webpage that accepts a parameter query:

Samples of parameters:

http://holland.mathcs.emory.edu/~cs377001/Web/employeeGet.php?query=select fname from employee
http://holland.mathcs.emory.edu/~cs377001/Web/employeeGet.php?query=select dname from department
(You can type the entire URL into your web-browser !!!)

An easier way to do this is to use this form:

Making URL requests with parameters to a Web server

There are 2 methods to send a request with parameters (data) to a web server:
(See: click here)

Difference between the GET and POST methods:

The GET method encodes the data as follows:
Example:
This method is not used in secure communication... (because it is inherently not secure !!!)
The POST method

The FORM HTML tag: an easy way to send parameters in a webpage

HTML FORM:

FORM = an HTML construct that can be used to:

Example: (web page with a FORM tag)

<html> <head> <title> HTML Form 1</title> </head> <body> <HR> <HR> <B> Form: </B> <HR> <P> <FORM ACTION="http://holland.mathcs.emory.edu/~cs377001/Web/echo.php" METHOD="GET or POST"> <p>Enter input: <input type="text" name="inp" size=40></p> <p><input type="submit" value="Press to send"></p> </FORM> </body> </html>

What the Form tag look like in a webpage:

Explanation:

The ACTION field specifies the PHP program (= URL) to run that will process the inputs obtained from the form.

Example:

ACTION="http://holland.mathcs.emory.edu/~cs377001/Web/echo.php"

will execute the follow program:

/home/cs377001/public_html/Web/echo.php

The <input type="text" ...> tag creates a (text) input field in the FORM

The attribute name="inp" indicates that:
The text in this field will be passed as the parameter named inp to the web-server
The attribute size=40 indicates that:

The <input type="submit" ... > tag creates an submit button in the FORM

If you want to see what this web page looks like, enter this URL in a web browser:
Or: click here
Enter some text in the input box and click submit