The GET Method
URL Encoding
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Besides allowing web browsers (or you pretending to be one) to get documents
from a web server, the GET
method also implements a method for a web browser to send optional search
parameters as well (it was used with ISINDEX HTML files originally).
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Search parameters were encoded in a special way for processing by the web
server.
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Here is how encoding works:
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The URL is differentiated from the first search parameter by a question
mark (?). In other words, a URL
generically looks like the following:
http://www.domain.com/dir/file?search parameters
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Since you may want to have multiple search parameters, the GET method specifies
that parameters are differentiated by placing an ampersand sign (&)
between them. Thus, the encoded URL above becomes something like the following:
http://www.domain.com/dir/file?search1&search2&search3
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Next, search parameters themselves are specified as "name/value pairs"
separated by an equal sign (=) such as in the following example that sets
the variable "lname" equal to "Sol" and the variable "fname" equal
to "Selena":
http://www.domain.com/dir/file?lname=Sol&fname=Selena
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Further, any spaces in the encoding string are replaced by plus signs (+)
as in the following example:
http://www.domain.com/dir/file?name=Selena+Sol&age=28
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Finally, any non-alphanumeric characters are replaced with their hexadecimal
equivalents that are escaped with the percent sign (%). For example, a
single quote character (') is encoded as %27 and a line break (which is
a carriage return plus a line feed) is encoded as %0D%0A. Thus, we might
see the following example that specifies that the variable pageName is
equal to "Selena Sol's Page":
http://www.domain.com/dir/file?pageName=Selena+Sol%27s+Page
Exercise
One
Table of Contents
Problems With the
GET Method
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