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PHP判断数组里是否有某值

in_array()

bool in_array ( $val, $array_name ,$mode )

in_array()输出布尔值真或假,作为某值是否在数组里的判断。

比如:

<?php 
$marks = array(100, 65, 70, 87); 
if ( in_array("100", $marks,true) ) 
{ 
echo "found";  
} 
else{ 
echo "not found"; 
} 
?> 

但是,in_array()对于有子数组的数组无能为力,如果需要查询更底层或更复杂的数组,需要构件一个自定义函数进行查询:

<?php
function in_array_recursive($needle, $haystack) {
$it = new RecursiveIteratorIterator(new RecursiveArrayIterator($haystack));
foreach($it AS $element) {
if($element == $needle) {
return true;
}
}
return false;
}

如此一来,我们就能使用 in_array_recursive() 代替 in_array() 进行子数组的查询,例如:

$array = Array
(
[0] => Array
(
[0] => 225
[1] => 226
[2] => 227
[3] => 228
[4] => 229
[5] => 230
[6] => 340
[7] => 355
)
[1] => Array
(
[0] => 313
[1] => 314
[2] => 315
[3] => 316
[4] => 318
[5] => 319
)
[2] => Array
(
[0] => 298
[1] => 301
[2] => 302
[3] => 338
)
)
if( in_array_recursive( 225 , $array ) ){
echo "found 225 in array";
}

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