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| Both sides previous revision Previous revision Next revision | Previous revision | ||
| docs:programming:php:php_notes [2007/03/23 14:13] – billh | docs:programming:php:php_notes [2008/08/03 00:25] (current) – external edit 127.0.0.1 | ||
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| </ | </ | ||
| + | |||
| + | |||
| + | ===== $PHP_SELF ===== | ||
| + | $PHP_SELF is a variable which represents the currently executing script (the name of the file you are viewing/ | ||
| ===== Dynamic Variables ===== | ===== Dynamic Variables ===== | ||
| Line 36: | Line 40: | ||
| echo ${$var[1]}; | echo ${$var[1]}; | ||
| </ | </ | ||
| + | |||
| ===== Objects ===== | ===== Objects ===== | ||
| Line 62: | Line 67: | ||
| } | } | ||
| </ | </ | ||
| - | More information is available at http://www.php.net/ | + | More information is available at: |
| + | * (PHP4) | ||
| + | * (PHP5) http:// | ||
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| * $this< | * $this< | ||
| * $this< | * $this< | ||
| + | |||
| + | |||
| + | |||
| + | ===== testing for variable existence ===== | ||
| + | <code php> | ||
| + | // note - a variable could be set, but set with no value | ||
| + | if(isset($var)) | ||
| + | // do something | ||
| + | |||
| + | // is the variable set and not empty | ||
| + | if(!empty($var)) | ||
| + | // do something | ||
| + | |||
| + | // using the variable name as a test is the same as !empty | ||
| + | if($var) | ||
| + | // do something | ||
| + | </ | ||
| + | |||
| ===== testing for string equality ===== | ===== testing for string equality ===== | ||
| < | < | ||
| + | // use this when testing for simple string equality | ||
| + | if($var == "match string" | ||
| + | // do something | ||
| + | |||
| + | // three equals (===) check for equality of value and type | ||
| + | // i.e. 0.0 == 0 (true) | ||
| + | // i.e. 0.0 === 0 (false) | ||
| + | if($var === "match string" | ||
| + | // do something | ||
| + | |||
| + | // strcasecmp and strcmp will return higher, lower or zero depending | ||
| + | // if the match string is considered higher, lower or equal | ||
| if(strcasecmp($var, | if(strcasecmp($var, | ||
| // do something | // do something | ||
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| ===== accessing class members from another function ===== | ===== accessing class members from another function ===== | ||
| * if you add a normal function in a file after a class has been defined, and you want to access the members of the class within the normal function, you need to declare the class as " | * if you add a normal function in a file after a class has been defined, and you want to access the members of the class within the normal function, you need to declare the class as " | ||
| + | |||
| + | ===== require/ | ||
| + | * if you use require or include, make sure to use a relative or full path to avoid duplicating a filename already in the php include path (such as DB.php) | ||
| + | |||