LU07.A09 - Basic caluclator with methods

Work type: Individual
Means of aid: only teaching materials, no websearch, no use of ai.
Timeframe: 50 Minutes
Expected result: A browser based calulator which can sum up 2 digits in the easiest way.

Take the solution of LU06.S08source-code and extend it

In LU06.S08 we were programming a basic calulator by manipulation the values directly when clicking the buttons. This is convenient, but limits the possibilities of the calculator significantly. For example handling the divided-by-zero operation can hardly be handled with events only.

Thus, it is basically a similar assignment, but this time by using methods:

to set values of diggit1, diggit2 and the operator
to calulate the result
to reset all values of the variables

A01: Copy the solution of LU06.s08 and name it LU07.s09.html
A02: Make sure to have
- the assignmen number in <h1> and
- the description in <h3>-format
A03: Safe it.

B01: method setDiggit1(number): It sets the value of the variable diggit1 to the clicked number (diggit-block 1).
B02: method setDiggit2(number): It sets the value of the variable diggit2 to the clicked number (diggit-block 2).
B03: method setOperator(op): It sets the value of the variable operator to the clicked operation, e.g +. Hint: further operations are possible.
B04: method calcResult(op): Performes the calculation correspondigly to the chosen operation, e.g. +.
B05: method reset(): Sets all variables to the initial values.

C01: A basic calculation, e.g. 3 + 3 = 6, compraises several variables and their initial values:
C02: Set in the data-area: * diggit1: 0
C03: operator: '+' (default operation is an addition)
C04: diggit2: 0
C05: result: 0

D01: When clicking on the diggit keys of block one the content will be saved in the variable diggit1
D02: But unlike in the previous task, this time the click triggers a method setDiggit1(dig1)
D03: Continue with the other three buttons in the same fashion.
D04: Check the result by displaying the content of the variable diggit1 on the display.

E01: When clicking the +-button the content will be saved in the variable operator
E02: Check the result by displaying the content of the variable operator on the screen.
Hint: The other three basic operations (subtraktion, multiplication, division) are conducted in the same way.

F01: When clicking on the button in diggit2-block, the content will be saved in the variable diggit2
F02: But unlike in the previous task, this time the click triggers a method setDiggit2(dig2)
F03: Continue with the other three buttons in the same fashion.
F04: Check the result by displaying the content of the variable diggit2 on the display.

G01: To execute our addition-operation we finally need a button ENTER. This triggers the method caldResult().
G02: All relevant variables (diggit1, operator, diggit2) are set know, we are ready to finalize our calculation.
G03: In the method calcResult we need to execute the calculation bases on the provided operator.
- If the operator is a + we calculate our result as this.result = this.diggit1 + this.diggit2„ * And subsequently, if the calculator is a minus-** the result is calculated as this.result = dthis.diggit1 - this.diggit2
- The Multiplication and the division a conducted in the same fashion.
G04: Finally have the result displayed on the screen to check the correctness of your efforts.