How to Convert a Character to a Number in Java

In Java, converting a character to a number can be a common task, especially when dealing with input from the user or parsing input data. This article provides a detailed explanation along with examples to help you understand the process of converting a character to a number in different scenarios.

Converting a Character to its Integer Value

When you want to convert a character to its integer value, which is its ASCII value, you can use simple arithmetic operations. Here's how you can do it:

Example 1: Direct Subtraction for ASCII Value

If you have a character and want to get its ASCII value, you can simply subtract the ASCII value of the character '0' from it. For example:

class Demo {
    public static void main(String[] args) {
        char ch  '3';
        // Converting ch to its int value
        int a  ch - '0';
        (a);
    }
}

Here, the character '3' is converted to its ASCII value by subtracting the ASCII value of '0'. The output will be 3.

Example 2: Using Character's ASCII Value Directly

If you have a character containing a numerical digit and you want to get the corresponding integer value, you can directly assign the character to an integer variable:

char a  '3';
int b  a;
(b);

This will also output 3, as the character '3' is stored as the integer value 51 in ASCII.

Using Predefined Methods for Conversion

Java provides useful methods to convert characters to numbers in a more straightforward manner. For instance, you can use the () method to convert a character to its numerical value.

Example 3: Using

class CharToInt {
    public static void main(String[] args) {
        char c  '5';
        char ch  '3';
        int n  (c);
        int m  (ch);
        (n); // Output: 5
        (m); // Output: 3
    }
}

The () method returns the numerical value of the given character, which is particularly useful for digits.

Conclusion

Converting a character to a number in Java can be done in various ways, depending on the specific requirements of your program. Whether you are dealing with ASCII values or numerical digits, the methods provided in this article should help you achieve your desired outcome efficiently.