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Web Programming

Notes end sub
</script>

Notes We cannot use the ASP script delimiters (<% and %>) to insert scripts in the Global.asa
file, we will have to put the subroutines inside the HTML <script> tag.

9.6 # include

The #include directive tells the preprocessor to treat the contents of a specified file as if those
contents had appeared in the source program at the point where the directive appears. You can
organize constant and macro definitions into include files and then use #include directives to
add these definitions to any source file. Include files are also useful for incorporating declarations
of external variables and complex data types. You need to define and name the types only once
in an include file created for that purpose.
#include “path-spec”
#include <path-spec>
The path-spec is a filename optionally preceded by a directory specification. The filename must
name an existing file. The syntax of the path-spec depends on the operating system on which the
program is compiled.
Both syntax forms cause replacement of that directive by the entire contents of the specified
include file. The difference between the two forms is the order in which the preprocessor searches
for header files when the path is incompletely specified.

Syntax Form Action

Quoted form This form instructs the preprocessor to look for include files in the
same directory of the file that contains the#include statement, and then
in the directories of any files that include (#include) that file. The
preprocessor then searches along the path specified by the /I compiler
option, then along paths specified by the INCLUDE environment
variable.
Angle-bracket form This form instructs the preprocessor to search for include files first
along the path specified by the /I compiler option, then, when
compiling from the command line, along the path specified by the
INCLUDE environment variable.

If the filename enclosed in double quotation marks is an incomplete path specification, the
preprocessor first searches the “parent” file’s directory. A parent file is the file containing
the #include directive. For example, if you include a file named file2 within a file
named file1, file1 is the parent file.
Include files can be “nested”; that is, an #include directive can appear in a file named by
another #include directive.

Example: File2, above, could includefile3. In this case, file1 would still be the parent
of file2 but would be the “grandparent” of file3.

When include files are nested and when compiling from the command line, directory searching
begins with the directories of the parent file and then proceeds through the directories of any

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