Zend supports the creation of true constants (as opposed to regular variables). Constants are accessed without the typical dollar sign ($) prefix and are available in all scopes. Examples include TRUE and FALSE, to name just two.
To create your own constants, you can use the macros in Table 33-6. All the macros create a constant with the specified name and value.
You can also specify flags for each constant:
CONST_CS - This constant's name is to be treated as case sensitive.
CONST_PERSISTENT - This constant is persistent and won't be "forgotten" when the current process carrying this constant shuts down.
// register a new constant of type "long" REGISTER_LONG_CONSTANT("NEW_MEANINGFUL_CONSTANT", 324, CONST_CS | CONST_PERSISTENT); |
Table 33-6. Macros for Creating Constants
Macro | Description |
REGISTER_LONG_CONSTANT(name, value, flags) REGISTER_MAIN_LONG_CONSTANT(name, value, flags) | Registers a new constant of type long. |
REGISTER_DOUBLE_CONSTANT(name, value, flags) REGISTER_MAIN_DOUBLE_CONSTANT(name, value, flags) | Registers a new constant of type double. |
REGISTER_STRING_CONSTANT(name, value, flags) REGISTER_MAIN_STRING_CONSTANT(name, value, flags) | Registers a new constant of type string. The specified string must reside in Zend's internal memory. |
REGISTER_STRINGL_CONSTANT(name, value, length, flags) REGISTER_MAIN_STRINGL_CONSTANT(name, value, length, flags) | Registers a new constant of type string. The string length is explicitly set to length. The specified string must reside in Zend's internal memory. |