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is_string

(PHP 4, PHP 5, PHP 7)

is_string — Find whether the type of a variable is string

Description

is_string ( mixed $var ) : bool

Finds whether the type of the given variable is string.

Parameters

var

The variable being evaluated.

Return Values

Returns true if var is of type string, false otherwise.

Examples

Example #1 is_string() example

<?php
$values = array(false, true, null, 'abc', '23', 23, '23.5', 23.5, '', ' ', '0', 0);
foreach ($values as $value) {
    echo "is_string(";
    var_export($value);
    echo ") = ";
    echo var_dump(is_string($value));
}
?>

The above example will output:

is_string(false) = bool(false)
is_string(true) = bool(false)
is_string(NULL) = bool(false)
is_string('abc') = bool(true)
is_string('23') = bool(true)
is_string(23) = bool(false)
is_string('23.5') = bool(true)
is_string(23.5) = bool(false)
is_string('') = bool(true)
is_string(' ') = bool(true)
is_string('0') = bool(true)
is_string(0) = bool(false)

See Also

  • is_float() - Finds whether the type of a variable is float
  • is_int() - Find whether the type of a variable is integer
  • is_bool() - Finds out whether a variable is a boolean
  • is_object() - Finds whether a variable is an object
  • is_array() - Finds whether a variable is an array

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Licensed under the Creative Commons Attribution License v3.0 or later.
https://www.php.net/manual/en/function.is-string.php