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How to determine whether a character is in an array in php
- PHPzOriginal
- 2023-04-19 11:37:35830browse
In PHP, there are many methods to determine whether a character is in an array.
1. Use the in_array() function
The in_array() function can be used to determine whether a value is in an array, and the return value is true or false.
Sample code:
$array = array('apple', 'banana', 'orange');
if (in_array('apple', $array)) {
echo 'yes';
} else {
echo 'no';
}
The output result is: yes
2. Use array_search() function
array_search() function can be used to find a value The position in the array, or false if it does not exist.
Sample code:
$array = array('apple', 'banana', 'orange');
$key = array_search('banana', $array);
if ($key !== false) {
echo 'yes';
} else {
echo 'no';
}
The output result is: yes
3. Use the in_array() function and strict parameters
The third of the in_array() function One parameter can specify whether case sensitivity is required. If case sensitivity is required, specify true.
Sample code:
$array = array('apple', 'banana', 'orange');
if (in_array('Apple', $array, true)) {
echo 'yes';
} else {
echo 'no';
}
The output result is: no
4. Use the array_search() function and strict parameters
The third of the array_search() function Each parameter can also specify whether it is case-sensitive.
Sample code:
$array = array('apple', 'banana', 'orange');
$key = array_search('Apple', $array, true);
if ($key !== false) {
echo 'yes';
} else {
echo 'no';
}
The output result is: no
5. Use the in_array() function and array_map() function
array_map() function Convert all values in an array to lowercase or uppercase before making a judgment.
Sample code:
$array = array('apple', 'banana', 'orange');
$lower_array = array_map('strtolower', $array);
if (in_array('apple', $lower_array)) {
echo 'yes';
} else {
echo 'no';
}
The output result is: yes
6. Use array_search() function and array_map() function
Similarly, use array_map( ) function can convert all the values in an array to lowercase or uppercase before searching.
Sample code:
$array = array('apple', 'banana', 'orange');
$lower_array = array_map('strtolower', $array);
$key = array_search('Apple', $lower_array);
if ($key !== false) {
echo 'yes';
} else {
echo 'no';
}
The output result is: yes
To sum up, you can use the in_array() function and array_search() function to determine whether a character is in the array. And the parameters of related functions are case-sensitive and other operations. In actual development, choosing the appropriate method according to the specific situation can improve code efficiency.
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