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is_string

is_string

(PHP 4, PHP 5, PHP 7)

is_string — Find whether the type of a variable is string

Description

bool is_string ( mixed $var )

Finds whether the type 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

← is_scalar

isset →

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https://secure.php.net/manual/en/function.is-string.php