how to add strings as numbers?

**Dixxon** · December 8th, 2013, 01:47 PM

hey

i am trying to add two strings as numbers, as an exampel :

String numb1 ="30";
String numb2 ="30";

where the answer would be 60 and not 3030. any ideas how to do that ?

**andbin** · December 8th, 2013, 01:49 PM

Originally Posted by Dixxon

i am trying to add two strings as numbers, as an exampel :

String numb1 ="30";
String numb2 ="30";

where the answer would be 60 and not 3030. any ideas how to do that ?

Convert (better to say "parse") String to int. See parseInt, static method of java.lang.Integer.

**Dixxon** · December 8th, 2013, 01:52 PM

will that work ? as the method i am using is a string method , looks like this

public static String add (String numb1, String nub2) 
 {
	 // any code
 }

**andbin** · December 8th, 2013, 02:00 PM

Originally Posted by Dixxon

will that work ?

How/where you encapsulate the sum of two string-numbers is not very much important. The important base concept is the conversion from String to int (or long or double or other primitive, you can choose). And I repeat: see the parseInt method of Integer.

**Dixxon** · December 8th, 2013, 02:13 PM

i think it would look like :

 public static String addera (String tal1, String tal2) 
 {
	 String Numb1= "30";
	 String Numb2 ="30";
	 int IntNumb1 = Integer.parseInt(Numb1);
	 int IntNumb2 = Integer.parseInt(Numb2);
	 return(IntNumb1 + IntNumb2);
 // gives an error "Type mismatch: cannot convert from int to String"
 }

PS: i am new to java so excuse my questions....

**andbin** · December 8th, 2013, 02:40 PM

Originally Posted by Dixxon

i think it would look like :

 return(IntNumb1 + IntNumb2);
 // gives an error "Type mismatch: cannot convert from int to String"

return "" + IntNumb1 + IntNumb2;

or (better)

return Integer.toString(IntNumb1 + IntNumb2);

or also (Integer.toString is called under the hood)

return String.valueOf(IntNumb1 + IntNumb2);

**Dixxon** · December 8th, 2013, 02:56 PM

oh yeah thanks , i got it work with String.valueOf()

but while adding 3333333333333 + 3 it gives me an error :

Exception in thread "main" java.lang.NumberFormatException: For input string: "3333333333"
at java.lang.NumberFormatException.forInputString(Unk nown Source)
at java.lang.Integer.parseInt(Unknown Source)
at java.lang.Integer.parseInt(Unknown Source)
at OperationerMedNaturligaHeltalGivnaSomTeckenstranga r.addera(OperationerMedNaturligaHeltalGivnaSomTeck enstrangar.java:60)
at OperationerMedNaturligaHeltalGivnaSomTeckenstranga r.main(OperationerMedNaturligaHeltalGivnaSomTecken strangar.java:19)

any ideas?

**andbin** · December 8th, 2013, 04:55 PM

Originally Posted by Dixxon

but while adding 3333333333333 + 3 it gives me an error :

Exception in thread "main" java.lang.NumberFormatException: For input string: "3333333333"

3333333333333 is more than the largest int value. An int is 32 bit, ranges from -2147483648 to +2147483647.

Originally Posted by Dixxon

any ideas?

Use long (64 bit). And please, see Long.parseLong method.

Thread: how to add strings as numbers?

LinkBack

Thread Tools

Display

how to add strings as numbers?

Related threads:

Re: how to add strings as numbers?

Re: how to add strings as numbers?

Re: how to add strings as numbers?

Re: how to add strings as numbers?

Re: how to add strings as numbers?

The Following User Says Thank You to andbin For This Useful Post:

Re: how to add strings as numbers?

Re: how to add strings as numbers?

Similar Threads

How to add the numbers in the following series?

How To: Add line numbers to your JTextArea

How to add strings to this Code?

How to add line numbers in Eclipse

How To: Add line numbers to your JTextArea