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Features of creating a calculator in the Delphi language

You can complete the process of creating a calculator that is similar to such an application in the Windows operating system if you know how to properly implement this process by using the Delphi programming language. The procedure itself is not complicated, but has its own characteristics.

The procedure for creating a calculator in the Delphi language begins with placing the necessary components on the form. Instead of a standard Button, you can use an element such as a BitButton. Its peculiarity lies in the fact that here on the buttons you can change the color of the font used. On each of the selected buttons, you need to arrange the necessary records and change their color through the Font property.

To display and enter numbers, you need to add a special Edit field. Through the MainMenu component, it is possible to create such options as "Help Call" and "About".


In the next step, you can start the process of declaring variables:


  • i – to store the first number to be entered;
  • p – to store the second number with which the mathematical operation will be performed;
  • r – to derive the result;
  • mode —a variable intended for the process of preserving the activity code.

To create the number buttons, use the following code:

Calculator in Delphi

Use this procedure to perform a process of describing all the buttons with numbers. When you create action buttons, the procedure for changing the digit of the number will be specified by the following piece of the program:

Calculator in Delphi

The program code for writing a button to add certain numbers will look like this:

Calculator in Delphi

As for writing subtraction, multiplication, and division buttons, their codes will look like this:

Calculator in Delphi

To extract the arithmetic square root and calculate the inverse proportionality function, the following commands are used:

Calculator in Delphi

To specify the procedure that will calculate the sine of a number, use the following code:

Calculator in Delphi

For cosine, everything will happen in the same way, but with the use of the appropriate function.
At the next stage, you should start creating a Form2 form, which will be used to display the necessary information about the program. Form2 will be used to create Help.
Having performed all the above actions, it is possible to create a fairly simple, but at the same time workable calculator that is able to perform elementary mathematical calculus.