PHP is_numeric Detects whether a variable is a number or a numeric string (Recommended learning: PHP Programming from Beginner to Master)
bool is_numeric ( mixed $var )
Returns TRUE if var is a number or numeric string, otherwise returns FALSE.
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For example 1:
<?php
$v = is_numeric ('58635272821786587286382824657568871098287278276543219876543') ? true : false;
var_dump ($v);
?>
The above script will output:
bool(true)Recommended related articles:
1.php determines whether a string is a number
2.How does php determine how many digits a number has?
3.php determines whether it is an integer
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For example 2:
<?php
$str="0";
$strTest=is_numeric(0);
var_dump($strTest);
?>
boolean true
//
function int_str($str){
if(is_numeric($str)){
$str = 'm'.$str;
}
return $str;
}The above is the detailed content of PHP determines whether it is a number. For more information, please follow other related articles on the PHP Chinese website!
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