Php/docs/class.splfixedarray
(PHP 5 >= 5.3.0, PHP 7)
简介
The SplFixedArray class provides the main functionalities of array. The main differences between a SplFixedArray and a normal PHP array is that the SplFixedArray is of fixed length and allows only integers within the range as indexes. The advantage is that it uses less memory than a standard array.
类摘要
SplFixedArray implements Iterator , ArrayAccess , Countable {
public __construct
([ int $size = 0
] )
public count ( ) : int
public static fromArray
( array $array
[, bool $save_indexes = true
] ) : SplFixedArray
public getSize ( ) : int
public key ( ) : int
public next ( ) : void
public offsetExists
( int $index
) : bool
public offsetUnset
( int $index
) : void
public rewind ( ) : void
public setSize
( int $size
) : bool
public toArray ( ) : array
public valid ( ) : bool
public __wakeup ( ) : void
}
范例
Example #1 SplFixedArray usage example
<?php// Initialize the array with a fixed length$array = new SplFixedArray(5);$array[1] = 2;$array[4] = "foo";var_dump($array[0]); // NULLvar_dump($array[1]); // int(2)var_dump($array["4"]); // string(3) "foo"// Increase the size of the array to 10$array->setSize(10);$array[9] = "asdf";// Shrink the array to a size of 2$array->setSize(2);// The following lines throw a RuntimeException: Index invalid or out of rangetry { var_dump($array["non-numeric"]);} catch(RuntimeException $re) { echo "RuntimeException: ".$re->getMessage()."\n";}try { var_dump($array[-1]);} catch(RuntimeException $re) { echo "RuntimeException: ".$re->getMessage()."\n";}try { var_dump($array[5]);} catch(RuntimeException $re) { echo "RuntimeException: ".$re->getMessage()."\n";}?>
以上例程会输出：
NULL int(2) string(3) "foo" RuntimeException: Index invalid or out of range RuntimeException: Index invalid or out of range RuntimeException: Index invalid or out of range
Table of Contents
- SplFixedArray::__construct — Constructs a new fixed array
- SplFixedArray::count — Returns the size of the array
- SplFixedArray::current — Return current array entry
- SplFixedArray::fromArray — Import a PHP array in a SplFixedArray instance
- SplFixedArray::getSize — Gets the size of the array
- SplFixedArray::key — Return current array index
- SplFixedArray::next — Move to next entry
- SplFixedArray::offsetExists — Returns whether the requested index exists
- SplFixedArray::offsetGet — Returns the value at the specified index
- SplFixedArray::offsetSet — Sets a new value at a specified index
- SplFixedArray::offsetUnset — Unsets the value at the specified $index
- SplFixedArray::rewind — Rewind iterator back to the start
- SplFixedArray::setSize — Change the size of an array
- SplFixedArray::toArray — Returns a PHP array from the fixed array
- SplFixedArray::valid — Check whether the array contains more elements
- SplFixedArray::__wakeup — Reinitialises the array after being unserialised
/* 方法 */