Answers for "how to know if a string is a number"

java how to check string is number

public static boolean isNumeric(String strNum) {
    if (strNum == null) {
        return false;
    }
    try {
        double d = Double.parseDouble(strNum);
    } catch (NumberFormatException nfe) {
        return false;
    }
    return true;
}

check if string is decimal java

Scanner in = new Scanner(System.in);
		
		String ip1 = in.nextLine();
		
		if( ip1.matches("^\d+\.\d+") ) 
			System.out.println(ip1+"----is a decimal number");
		else
			System.out.println(ip1+"----is a not decimal number");

check if the given string is a number

//Add this to your code and call
static private boolean isMyNumber(String s){
        try{
            Integer.parseInt(s);
            return true;
        }catch (Exception e){
            return false;
        }
    }

check if string can be a number and then make a number

if(Number(myNumber) != NaN){
	myNumber = Number(myNumber);
}