在多维数组中查找值

Question

I have to find value in a multidimensional array, size of array is not defined. Let suppose user enters 1601 , result will be 011. and if 1605 , the result will be 015 according to array

   array (size=6)
      0 => 
        array (size=2)
          0 => string 'Zipcode' (length=7)
          1 => string 'Territory Code' (length=14)
      1 => 
        array (size=2)
          0 => string '1601' (length=4)
          1 => string '011' (length=3)
      2 => 
        array (size=2)
          0 => string '1602' (length=4)
          1 => string '012' (length=3)
      3 => 
        array (size=2)
          0 => string '1603' (length=4)
          1 => string '013' (length=3)
      4 => 
        array (size=2)
          0 => string '1604' (length=4)
          1 => string '014' (length=3)
      5 => 
        array (size=2)
          0 => string '1605' (length=4)
          1 => string '015' (length=3)

Answer 1

If Zipcode is unique then you can do:

echo array_column($array, 1, 0)[1601];

Or if Territory Code is unique:

echo array_search(1601, array_column($array, 0, 1), true);

array_column() extracts a column from the multi-dimensional array to create a one dimensional array.

array array_column ( array $input , mixed $column_key [, mixed $index_key = null ] )

The second parameter $column_key defining which column you want to get from the multidimensional array as values into the one dimensional array. And the third parameter $index_key defining which column you want to use as keys for the one dimensional array which you get back. If $index_key is not defined, the array will be numerical enumerated.

First code example

So the first example extracts an array such as:

array(1601 => '011', 1602 => '012')

Using the value 1601 as the key you get the desired output 011.

Second code example

The second example uses an array such as:

array('011' => 1601, '012' => 1602)

And searches for 1601 with array_search() to get the key 011, which is the desired output.

See these two examples for what the second and third parameters do:

print_r(array_column($array, 1, 0));
print_r(array_column($array, 0, 1));