How do i...understand this piece of code

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1.00/5 (1 vote)

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I was creating a calculator and I don't understand the code below

Let outputScreen = document.getElementById("input")

Function display(num){
outputScreen.value += num;
}

Function calculate(){
try{
outputScreen.value = eval(outputScreen.value);
}
catch(err){
alert("invalid")
}
}

Please explain the javascript code

What I have tried:

I have tried searching on Google for an explanation but am not understanding them

Posted 30-Jul-21 8:33am

This be Me

Updated 30-Jul-21 22:06pm

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Richard MacCutchan 31-Jul-21 4:51am

It's called 'learning'. Trying to become a programmer before you have properly studied, and learnt the language, is just a waste of your time.

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SeeSharp2 · Answer 1 · 2021-07-30T08:52:00

These are very basic javascript commands. You won't be able to write a calculator if you do not understand the basics.

Let outputScreen = document.getElementById("input") // This gets an element from your page with an id of "input" and stores it in a variable named outputScreen. This is self explanatory.

Function display(num){
outputScreen.value += num;
}

This is a function that you pass a value into and it adds it to whatever is in the input element.

For eval, see JavaScript eval() Function[^]

Richard MacCutchan · Answer 2 · 2021-07-30T22:06:00

Solution 2

See JavaScript Tutorial[^]

Posted 30-Jul-21 22:06pm

Richard MacCutchan