Please, How I check if the string digits “number” or not ? “Java”

Question

I have a string variable enters from console because I need check the length but in the same time I want check if it digit or not

Answer 1

You need to make a Boolean function which return true if string you entered can parse to any other numeric data type. Like this:

public static Boolean checkstr(String str)

try{
Double.parseDouble(str);
return True;
}
catch(Exception e)
{
Return False
}

Do this after you find the length of string.
Because this function will convert your string to number and then you can't use
.length() method on your string.
:)

Answer 2

myObject.getClass().getName(); // Its show type of your object.

Answer 3

Did you mean you want to check each character in the string for being a digit (0-9)?
Why you tagged 'iostream'? isn't that C++ header file?