ArraysPodręcznik PHPPoprzedniRozdział 33. Creating VariablesNastępnyArrays Arrays are stored using Zend's internal hash tables, which can be accessed using the zend_hash_*() API. For every array that you want to create, you need a new hash table handle, which will be stored in the ht member of the zval.value container. There's a whole API solely for the creation of arrays, which is extremely handy. To start a new array, you call array_init(). zval *new_array; MAKE_STD_ZVAL(new_array); array_init(new_array); array_init() always returns SUCCESS. To add new elements to the array, you can use numerous functions, depending on what you want to do. Tabela 33-1, Tabela 33-2 and Tabela 33-3 describe these functions. All functions return FAILURE on failure and SUCCESS on success. Tabela 33-1. Zend's API for Associative ArraysFunctionDescription add_assoc_long(zval *array, char *key, long n);() Adds an element of type long. add_assoc_unset(zval *array, char *key);()Adds an unset element. add_assoc_bool(zval *array, char *key, int b);() Adds a Boolean element. add_assoc_resource(zval *array, char *key, int r);() Adds a resource to the array. add_assoc_double(zval *array, char *key, double d);() Adds a floating-point value. add_assoc_string(zval *array, char *key, char *str, int duplicate);() Adds a string to the array. The flag duplicate specifies whether the string contents have to be copied to Zend internal memory. add_assoc_stringl(zval *array, char *key, char *str, uint length, int duplicate); () Adds a string with the desired length length to the array. Otherwise, behaves like add_assoc_string(). add_assoc_zval(zval *array, char *key, zval *value);()Adds a zval to the array. Useful for adding other arrays, objects, streams, etc...Tabela 33-2. Zend's API for Indexed Arrays, Part 1FunctionDescriptionadd_index_long(zval *array, uint idx, long n);()Adds an element of type long.add_index_unset(zval *array, uint idx);()Adds an unset element.add_index_bool(zval *array, uint idx, int b);()Adds a Boolean element.add_index_resource(zval *array, uint idx, int r);()Adds a resource to the array.add_index_double(zval *array, uint idx, double d);()Adds a floating-point value.add_index_string(zval *array, uint idx, char *str, int duplicate);()Adds a string to the array. The flag duplicate specifies whether the string contents have to be copied to Zend internal memory.add_index_stringl(zval *array, uint idx, char *str, uint length, int duplicate);()Adds a string with the desired length length to the array. This function is faster and binary-safe. Otherwise, behaves like add_index_string()().add_index_zval(zval *array, uint idx, zval *value);()Adds a zval to the array. Useful for adding other arrays, objects, streams, etc...Tabela 33-3. Zend's API for Indexed Arrays, Part 2FunctionDescriptionadd_next_index_long(zval *array, long n);()Adds an element of type long.add_next_index_unset(zval *array);()Adds an unset element.add_next_index_bool(zval *array, int b);()Adds a Boolean element.add_next_index_resource(zval *array, int r);()Adds a resource to the array.add_next_index_double(zval *array, double d);()Adds a floating-point value.add_next_index_string(zval *array, char *str, int duplicate);()Adds a string to the array. The flag duplicate specifies whether the string contents have to be copied to Zend internal memory.add_next_index_stringl(zval *array, char *str, uint length, int duplicate);()Adds a string with the desired length length to the array. This function is faster and binary-safe. Otherwise, behaves like add_index_string()().add_next_index_zval(zval *array, zval *value);()Adds a zval to the array. Useful for adding other arrays, objects, streams, etc... All these functions provide a handy abstraction to Zend's internal hash API. Of course, you can also use the hash functions directly - for example, if you already have a zval container allocated that you want to insert into an array. This is done using zend_hash_update()() for associative arrays (see Przykład 33-3) and zend_hash_index_update() for indexed arrays (see Przykład 33-4): Przykład 33-3. Adding an element to an associative array.zval *new_array, *new_element; char *key = "element_key"; MAKE_STD_ZVAL(new_array); MAKE_STD_ZVAL(new_element); array_init(new_array); ZVAL_LONG(new_element, 10); if(zend_hash_update(new_array->value.ht, key, strlen(key) + 1, (void *)&new_element, sizeof(zval *), NULL) == FAILURE) { // do error handling here } Przykład 33-4. Adding an element to an indexed array.zval *new_array, *new_element; int key = 2; MAKE_STD_ZVAL(new_array); MAKE_STD_ZVAL(new_element); array_init(new_array); ZVAL_LONG(new_element, 10); if(zend_hash_index_update(new_array->value.ht, key, (void *)&new_element, sizeof(zval *), NULL) == FAILURE) { // do error handling here } To emulate the functionality of add_next_index_*(), you can use this: zend_hash_next_index_insert(ht, zval **new_element, sizeof(zval *), NULL) Note: To return arrays from a function, use array_init() and all following actions on the predefined variable return_value (given as argument to your exported function; see the earlier discussion of the call interface). You do not have to use MAKE_STD_ZVAL on this. Tip: To avoid having to write new_array->value.ht every time, you can use HASH_OF(new_array), which is also recommended for compatibility and style reasons. PoprzedniSpis treściNastępnyBooleansPoczątek rozdziałuObjects