查人人中国名人网韩剧男与女在线观看:怎么判断PHP中的变量为数值型
来源：百度文库 编辑：查人人中国名人网 时间：2024/04/30 16:19:47
$b=0; //或$b=20;
现在我要判断$b 为数值，该怎么判断？
$a="a";
$b=0; //或$b=20;
if(is_numeric($b))
{
echo "Number";
}
else
{
echo "Not Number";
}
is_numeric($a);
是返回为TRUE 不是返回为FALSE
is_numeric
(PHP 4, PHP 5)
is_numeric -- Finds whether a variable is a number or a numeric string
Description
bool is_numeric ( mixed var )
Finds whether the given variable is numeric. Numeric strings consist of optional sign, any number of digits, optional decimal part and optional exponential part. Thus +0123.45e6 is a valid numeric value. Hexadecimal notation (0xFF) is allowed too but only without sign, decimal and exponential part.
Parameters
var
The variable being evaluated.
Return Values
Returns TRUE if var is a number or a numeric string, FALSE otherwise.
See Also
ctype_digit()
is_bool()
is_null()
is_float()
is_int()
is_string()
is_object()
is_array()