如何检查数字值

Question

how can i check in PHP a value for a number? What kind is better? Check ctype_digit() for a string automatically?

<?php 
if(ctype_digit($value)){
echo 'Yes';
} else {
echo 'No';
}

if(is_string($value) && ctype_digit($value)){
echo 'Yes';
} else {
echo 'No';
}
?>

Answer 1

要检查变量是数字还是数字字符串，请使用is_numeric函数：

echo (is_numeric($value))? 'yes' : 'no';

Answer 2

You can use the gettype() method which returns the variable type as a string, or you can just use is_string(), is_int(), is_float(), is_object(), is_array(), etc. to evaluate if the variable is of a given type.

You can see the full documentation here: http://php.net/manual/en/function.gettype.php