PHP Array method

Finding, filtering, and searching array elements are some of the common features of array manipulation. Here are a few related functions.

In_array () function

The In_array () function searches for a specific value in an array rollup and returns True if this value is found, otherwise false. The form is as follows:

1	boolean in_array(mixed needle,arrayhaystack[,boolean strict]);

Look at the following example, look for the variable if Apple is already in the array, and if so, output a piece of information:

1	$fruit= "apple";

2	$fruits= array("apple","banana","orange","pear");

3	if( in_array($fruit,$fruits) )

4	echo"$fruit 已经在数组中";

The third parameter is optional, which forces In_array () to consider the type when searching.

Array_key_exists () function

If a specified key is found in an array, the function array_key_exists () returns True, otherwise false is returned. The form is as follows:

1	boolean array_key_exists(mixed key,arrayarray);

The following example searches for Apple in the array key and, if found, outputs the color of the fruit:

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:

1	apple‘s color is red

Array_search () function

The Array_search () function searches for a specified value in an array, returns the corresponding key if found, otherwise returns false. The form is as follows:

1	mixed array_search(mixed needle,arrayhaystack[,boolean strict])

The following example searches for a specific date in $fruits (December 7) and, if found, returns information about the corresponding state:

1	$fruits["apple"] = "red";

2	$fruits["banana"] = "yellow";

3	$fruits["watermelon"]="green";

4	$founded= array_search("green", $fruits);

5	if($founded)

6	printf("%s was founded on %s.",$founded, $fruits[$founded])

The results of the program run as follows:

1	watermelon was founded on green.

Array_keys () function

The Array_keys () function returns an array that contains all the keys found in the searched array. The form is as follows:

1	arrayarray_keys(arrayarray[,mixed search_value])

If the optional parameter search_value is included, only the key that matches the value is returned. The following example outputs all the arrays found in the $fruit array:

1	$fruits["apple"] = "red";

2	$fruits["banana"] = "yellow";

3	$fruits["watermelon"]="green";

4	$keys= array_keys($fruits);

5	print_r($keys);

The results of the program run as follows:

1	Array ( [0] => apple [1] => banana [2] => watermelon )

Array_values () function

The Array_values () function returns all the values in an array and automatically provides a numeric index for the returned array. The form is as follows:

1	arrayarray_values(arrayarray)

The following example gets the values of each element found in $fruits:

1	$fruits["apple"] = "red";

2	$fruits["banana"] = "yellow";

3	$fruits["watermelon"]="green";

4	$values= array_values($fruits);

5	print_r($values);

The results of the program run as follows:

1	Array ( [0] => red [1] => yellow [2] => green )

Original link: http://www.nowamagic.net/librarys/posts/php/44

PHP Array method