[PHP] Return to the basics (Array related functions), return to array

[PHP] Return to the basics (Array related functions), return to array_PHP tutorial

WBOY

Release： 2016-07-12 08:52:29

Original

793 people have browsed it

[PHP] Return to the basics (Array related functions), return to array

Use the function array_keys() to get all the keys in the array, parameters: array

<span>$arr</span>=<span>array</span><span>();
</span><span>$arr</span>['one']="one"<span>;
</span><span>$arr</span>['two']="two"<span>;
</span><span>$arr</span>['three']="three"<span>;

</span><span>$newArr</span>=<span>array_keys</span>(<span>$arr</span><span>);
</span><span>print_r</span>(<span>$newArr</span><span>);
</span><span>//</span><span>Array ( [0] => one [1] => two [2] => three )</span>

Copy after login

Use the function array_values() to get all the values in the array. Parameters: array

<span>$arr</span>=<span>array</span><span>();
</span><span>$arr</span>[20]="one"<span>;
</span><span>$arr</span>[30]="two"<span>;
</span><span>$arr</span>[40]="three"<span>;

</span><span>$newArr</span>=<span>array_values</span>(<span>$arr</span><span>);
</span><span>print_r</span>(<span>$newArr</span><span>);
</span><span>//</span><span>Array ( [0] => one [1] => two [2] => three )</span>

Copy after login

Use the function array_map() to call a custom function for each element. Parameters: String type function name, array

<span>$arr</span>=<span>array</span><span>();
</span><span>$arr</span>[0]="one"<span>;
</span><span>$arr</span>[1]="two"<span>;
</span><span>$arr</span>[2]="three"<span>;
</span><span>function</span> test(<span>$v</span><span>){
    </span><span>return</span> <span>$v</span>." Hello"<span>;
}
</span><span>$newArr</span>=<span>array_map</span>("test",<span>$arr</span><span>);
</span><span>print_r</span>(<span>$newArr</span><span>);
</span><span>//</span><span>Array ( [0] => one Hello [1] => two Hello [2] => three Hello )</span>

Copy after login

Use the function array_merge() to merge two arrays into one, parameters: array, array

When associative arrays are merged, those with the same key will be overwritten by the subsequent array

When index arrays are merged, they will be connected together to form a new array

<span>$arr</span>=<span>array</span><span>();
</span><span>$arr</span>[0]="one"<span>;
</span><span>$arr</span>[1]="two"<span>;
</span><span>$arr</span>[2]="three"<span>;

</span><span>$arr1</span>=<span>array</span><span>();
</span><span>$arr</span>[3]="taoshihan1"<span>;
</span><span>$arr</span>[4]="taoshihan2"<span>;
</span><span>$arr</span>[5]="taoshihan3"<span>;

</span><span>$newArr</span>=<span>array_merge</span>(<span>$arr</span>,<span>$arr1</span><span>);
</span><span>print_r</span>(<span>$newArr</span><span>);
</span><span>//</span><span>Array ( [0] => one [1] => two [2] => three [3] => taoshihan1 [4] => taoshihan2 [5] => taoshihan3 )</span>

<span>$arr</span>=<span>array</span>("one","two","three"<span>);
</span><span>$arr1</span>=<span>array</span>("4","5","6"<span>);
</span><span>$newArr</span>=<span>array_merge</span>(<span>$arr</span>,<span>$arr1</span><span>);
</span><span>print_r</span>(<span>$newArr</span><span>);
</span><span>//</span><span>Array ( [0] => one [1] => two [2] => three [3] => 4 [4] => 5 [5] => 6 )</span>

Copy after login

Use the function ksort() to sort by key name. Note that no new array is returned, but the original array

<span>$arr</span>=<span>array</span>("2"=>"taoshihan2","1"=>"taoshihan1","3"=>"taoshihan3"<span>);
</span><span>ksort</span>(<span>$arr</span><span>);
</span><span>print_r</span>(<span>$arr</span><span>);
</span><span>//</span><span>Array ( [1] => taoshihan1 [2] => taoshihan2 [3] => taoshihan3 )</span>

Copy after login

Use the function array_search() to search for a certain key value and return the corresponding key

<span>$arr</span>=<span>array</span>("2"=>"taoshihan2","1"=>"taoshihan1","3"=>"taoshihan3"<span>);
</span><span>echo</span> <span>array_search</span>("taoshihan1",<span>$arr</span><span>);
</span><span>//</span><span> 1</span>

Copy after login