Search program code for arrays in php

Example

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<? Php $ People = array ("Peter", "Joe", "Glenn", "Cleveland "); If (in_array ("Glenn", $ people ))   { Echo "Match found ";   } Else   { Echo "Match not found ";   } ?>

Output:

Match found.

Array_key_exists () function
If a specified key is found in an array, the array_key_exists () function returns true; otherwise, false. The format is as follows:

1 boolean array_key_exists (mixed key, array );

The following example searches for apple in the array key. If it is found, the color of the fruit is output:

 

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1 $ fruit ["apple"] = "red "; 2 $ fruit ["banana"] = "yellow "; 3 $ fruit ["pear"] = "green "; 4 if (array_key_exists ("apple", $ fruit )){ 5 printf ("apple's color is % s", $ fruit ["apple"]); 6}

The result of executing this code is as follows:

1 apple's color is red

Array_search () function

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$ Fruits ["apple"] = "red "; $ Fruits ["banana"] = "yellow "; $ Fruits ["watermelon"] = "green "; $ Founded = array_search ("green", $ fruits ); If ($ founded) Printf ("% s was founded on % s.", $ founded, $ fruits [$ founded])

Array_keys () function

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$ Fruits ["apple"] = "red "; $ Fruits ["banana"] = "yellow "; $ Fruits ["watermelon"] = "green "; $ Keys = array_keys ($ fruits ); Print_r ($ keys );

The methods above can only search for one-dimensional data.

1. Search for the key value of a multi-dimensional array in php

For example:

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$ Foo [1] ['A'] ['XX'] = 'bar 1 '; $ Foo [1] ['B'] ['XX'] = 'bar 2 '; $ Foo [2] ['A'] ['BB '] = 'bar 3 '; $ Foo [2] ['A'] ['yy'] = 'bar 4 '; $ Foo [3] ['c'] ['DD'] = 'bar 3 '; $ Foo [3] ['F'] ['GG '] = 'bar 3 '; $ Foo ['info'] [1] = 'bar 5 ';

How can I find bar 3. There are three results, and all three results are required. Let's look at the following function:
Bytes -------------------------------------------------------------------------------------------------------------------------------

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Function array_search_re ($ needle, $ haystack, $ a = 0, $ nodes_temp = array ()){ Global $ nodes_found; $ A ++; Foreach ($ haystack as $ key1 => $ value1 ){ $ Nodes_temp [$ a] = $ key1; If (is_array ($ value1 )){ Array_search_re ($ needle, $ value1, $ a, $ nodes_temp );     } Else if ($ value1 ===$ needle ){ $ Nodes_found [] = $ nodes_temp;     } } Return $ nodes_found; }

Else ---------------------------------------------------------------------------------------------------------------------------------
This function can return all the content to be found above to the output key name.

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$ Result = array_search_re ('Bar 3', $ foo ); Print_r ($ result ); The output result is as follows: Array ([0] => Array ([1] => 2 [2] => a [3] => bb) [1] => Array ([1] => 3 [2] => c [3] => dd) [2] => Array ([1] => 3 [2] => f [3] => gg)         )

1 php search for the key name of a multi-dimensional array

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Function array_search_key ($ needle, $ haystack ){ Global $ nodes_found; Foreach ($ haystack as $ key1 => $ value1 ){   If ($ key1 ===$ needle ){   $ Nodes_found [] = $ value1;           } If (is_array ($ value1 )){ Array_search_key ($ needle, $ value1 );     }       } Return $ nodes_found; } $ Result = array_search_key ('A', $ foo ); Print_r ($ result ); The output result is as follows:   Array ( [0] => Array         ( [Xx] => bar 1         ) [1] => Array         ( [Bb] => bar 3         ) [2] => Array         ( [Yy] => bar 4         ) )

Multi-dimensional data search can be implemented through traversal.