Как преобразовать char в int
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Как преобразовать char в int

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Char to Int in Java

There are different ways to convert a character to its corresponding integer representation.

  • Assigning a character to an integer-type variable gives the ASCII value of the character.
  • Use Character.getNumericValue() method
  • Convert the character to a String using String.valueOf() method and use Integer.parseInt() method.
  • Subtract '0' from the character.

How to convert char to int in Java?

Sometimes we need to perform operations on integer values, here in this case it may be possible that the int value is stored in a char data type. In this situation, we first need to convert the char value to its corresponding integer value and then do the required operation.

The primitive data type can be converted from char to int data type in java using several ways:-

  1. Using ASCII values: We can automatically convert a character to its ASCII value by using implicit typecasting.
  2. Character.getNumericValue(): We can convert char to int using getNumericValue() method of the Character class.
  3. Using parseInt() method with String.valueOf(): We can convert char to int in java by converting char to string using String.valueOf() and then converting string to int using Integer.parseInt() method.
  4. Subtracting with '0': we can convert char to int by subtracting with 0 , this works on the concept of ASCII values.

Method 1: Using ASCII values

American Standard Code for Information Interchange is an encoding format used to store characters on a computer, it is a 7 — bit character set containing 128 characters.

In Java programming language we have implicit typecasting, i.e if we store the value of a smaller datatype to a variable of the larger datatype, then the value is automatically converted. This means that the variable is implicitly typecasted into a larger datatype variable.



  • So in this example variable first is implicitly typecasted to int datatype and then stored in second variable.
  • So now if we print the second variable it will print 53 . This is because we have assigned the char variable first to the int variable second and we get the ASCII value of 5 i.e. 53.

Example: 53-48 = 5

Below is the java program to convert char to int in java using the ASCII value:-


Method 2: Using Character.getNumericValue()

In Java, we have a method getNumericValue() inside the Character class. This method returns an int value which is the encoding of a Unicode character.


This method takes an argument of char datatype and returns the corresponding int value.



Method 3: parseInt() method with String.valueOf()

In java we can also convert from char to int java using the parseInt() and String.valueOf() methods.

  • The String.valueOf(): method converts a char datatype variable into a string datatype variable and,
  • Integer.parseInt(): method is used to convert string into an int datatype.

The method valueOf() belongs to String class and parseInt() method belongs to Integer class.




  • Here in this example, ch1 is first converted to string using String.valueOf() and then it is converted to int using Integer.parseInt() .
  • Similar operations are performed with ch2 character as well.

Method 4: Subtraction with '0':

In Java we can also convert the numeric value stored in a char to int datatype by subtracting it with the character 0 (zero). This is based on the concept of ASCII values.

If we want to convert char to int, we will subtract '0' from the character.

How To Convert Char to Int in C++

Are you looking to know how to convert Char to Int in C++? This article will show you the different ways to convert Char to Int.

In C++, most of the Char and Integer values can be represented by ASCII [1] values. Hence if you know the ASCII values for the number that are currently represented in char then you can easily convert those into integers.

Convert Char to Int in C++ Using ASCII Values

Let us see the below example code of how you can convert the number represented in Char to an integer value.


As you can see in the above code, ‘9’ was represented in char, and then with the use of typecasting the char value that reads it in ASCII form and then converts it to an integer value. Hence if you are aware that the char value can be represented in the ASCII value then only you can use this method and it would work.

Convert Char to Int Using Subtraction

This method you can use if you have a character that cannot be represented in ASCII value for example number 20. Hence to convert the char ’20’ in integer we need to use the subtraction method that will provide the ASCII for each digit and then we can add those to get the actual number.

Let us see in the below example code the usage of subtraction to get the Integer from Char in C++.


As per the above code, example — ‘0’ is equivalent to ((int)example) — ((int)’0′), which means the ASCII values of the characters are subtracted from each other. Since 0 comes directly before 1 in the ASCII table (and so on until 9 ), the difference between the two gives the number that the character a represents.

How To Convert Char to Int in C++

Convert Char* To Int in C++

If you want to convert char* to int in C++ when char* represents the number. And if the char* variable does not represent number then the below methods will not work.

Let us check in below example code below how you can change the char* to Int in C++.


As you can see in the above I was able to convert the char* to int using the string stream library. But this method is not 100% secure and you will receive a warning in C++ that you should not convert string to char*.

But if you still want to convert the char* to int ignoring the warning then you can use the above code to resolve this problem.

Wrap Up

I hope you got the answer related to how to convert char to int in C++. I have discussed two methods above that you can use directly to do the conversion.

Let me know in the comment section if you have found any method that is better than the one discussed above I will be happy to add it here.

If you liked the above tutorial then please follow us on Facebook and Twitter. Let us know the questions and answer you want to cover in this blog.

Преобразовать char в int в C#

В этом посте будет обсуждаться, как преобразовать char в int в C#.

1. Использование Char.GetNumericValue() метод

Рекомендуемый подход заключается в использовании встроенного GetNumericValue() метод для преобразования числового символа Unicode в его числовой эквивалент.

Следующий пример демонстрирует работу GetNumericValue() метод. Он ожидает символьное представление числового значения и возвращает двойное значение. Приведение необходимо для преобразования значения double в int.

Convert char to int in C and C++

a — ‘0’ is equivalent to ((int)a) — ((int)’0′) , which means the ascii values of the characters are subtracted from each other. Since 0 comes directly before 1 in the ascii table (and so on until 9 ), the difference between the two gives the number that the character a represents.

lucidbrot's user avatar

Well, in ASCII code, the numbers (digits) start from 48. All you need to do is:

Or, since the character ‘0’ has the ASCII code of 48, you can just write:

ib.'s user avatar

Vlad Isoc's user avatar

C and C++ always promote types to at least int . Furthermore character literals are of type int in C and char in C++.

You can convert a char type simply by assigning to an int .

char is just a 1 byte integer. There is nothing magic with the char type! Just as you can assign a short to an int, or an int to a long, you can assign a char to an int.

Yes, the name of the primitive data type happens to be "char", which insinuates that it should only contain characters. But in reality, "char" is just a poor name choice to confuse everyone who tries to learn the language. A better name for it is int8_t, and you can use that name instead, if your compiler follows the latest C standard.

Though of course you should use the char type when doing string handling, because the index of the classic ASCII table fits in 1 byte. You could however do string handling with regular ints as well, although there is no practical reason in the real world why you would ever want to do that. For example, the following code will work perfectly:

You have to realize that characters and strings are just numbers, like everything else in the computer. When you write ‘a’ in the source code, it is pre-processed into the number 97, which is an integer constant.

So if you write an expression like

this is actually equivalent to

which is then going through the C language integer promotions

and then truncated to a char to fit the result type

There’s a lot of subtle things like this going on between the lines, where char is implicitly treated as an int.

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