Specifications

Advanced PHP Techniques

ART IV

448

Some useful PHP functions and features do not fit into any particular category. This chapter

will explain these features.

We’ll look at

• Using magic quotes

• Evaluating strings with eval()

• Terminating execution: die and exit

• Serialization

• Getting information about the PHP environment

• Temporarily altering the runtime environment

• Loading PHP extensions

• Source highlighting

Using Magic Quotes

You have probably noticed that you need to be careful when using quote symbols (‘ and “) and

back slashes (\) within strings. PHP will get confused by an attempted string statement like

echo “color = “#FFFFFF””;

and give a parse error. To include quotes inside a string, use the quote type that is different

from the quotes enclosing the string. For example

echo “color = ‘#FFFFFF’”;

echo ‘color = “#FFFFFF”’;

will both be valid.

The same problem occurs with user input, as well as input and output to, or from, other

programs.

Trying to run a mysql query like

insert into company values (‘Bob’s Auto Parts’);

will produce similar confusion in MySQL’s parser.

We have already looked at the use of addslashes() and stripslashes() that will escape out

any single quote, double quote, backslash and NUL characters.

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