Homework 3 JavaScript and the Document Object Model

Homework 3 JavaScript and the Document Object Model
1 Assignment Objectives ThegoalofthisassignmentistohelpyouunderstandhowJavaScriptandHTML connect to achieve webpage functionality. You will be making a calculator that functions based on the clicking of different DOM elements. This is what the calculator looks like:
Here is a the gif with the calculator functionality: Gfycat
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2 Setup Forthisassignment,youwillbeeditingonefile,soltions,whichislinkedto inexhtml. DO OT edit the HTML in any way, you only need to write the JavaScript functions. In the soltions, you will find skeleton code for the different functions you have to create. You will also be utilizing global variables to manage the state of your calculator. It is recommended to have a global reslt value to hold the current value of the calculator, a global rrentp value to represent the operation being used, and a global ber value to hold the previous value to compute with the reslt for each operation. 3 Functions You are responsible for the following functions: 3.1 resetCalc() This function will reset all values of the calculator, including the current result, the buffer value and the current operation. 3.2 setDisplay(str) This function will find the element that has the iotpt property and change the inner text of that element to reflect the current result of the calculator. 3.3 getResult() This function will return the current result of your calculator. (Make sure it’s a number, not a string!) 3.4 pressNum(num) This function is attached to every number button element like so: btton onlikpressm11btton This function will append the current number to the current result value. Make sure to restrict this value to be between the minimum (-999999999) and maximum (999999999). 3.5 pressp(op) This function is attached to every operation element like so: btton lssopertion onlikpressp-minsbtton
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This function will move the current result value to a temporary buffer and set thecurrentresulttozero. Ifanumberhasnotbeenenteredbetweenoperations, this function should only change the operation, and keep the same buffer value (not move 0 to the buffer). 3.6 pressquals() Shouldcomputetheoperationbetweenthebuffervalueandcurrentresultvalue based on the current operation. If there is no current operation, do nothing. If a user attempts an invalid operation (such as 0 ÷ 0) the calculator should display ”ERROR”. Also, be sure to once again check that your result value is restricted between the minimum (-999999999) and maximum (999999999).