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JavaScript

olu adesina
olu adesina
23,007 Points
Posted by olu adesina
olu adesina
23,007 Points

changing boolean values in two dimensional arrays ?

hi guys

using a for loop i'm attempting to change 1 of 3 values in an array from false to true is this possible

/var questionsAnswers contains three values. A question and answer and false value which will change when the correct answer is submited///

var questionsAnswers =[ ['What is the capital of England? ','LONDON',false],

['what is the capital of France?','PARIS',false],

['What organ pumps blood around the body?','HEART',false]

];

var ask; var rightAnswers = 0

function print(message) { document.write(message);

}

for(x=0;x<questionsAnswers.length;x+=1) { ask=prompt(questionsAnswers[x][0]);

if(ask.toUpperCase()==questionsAnswers[x][1]) { questionsAnswers[x][2]=true // this is where the false statment is meant to change to true

rightAnswers+=1;

}

}

print('you got '+rightAnswers+' questions right!<BR><BR>')

print('YOU GOT THESE QUESTIONS CORRECT <br><br>') for(y=0;y<questionsAnswers.length;y+=1) {
/***************************************** the if statement below is meant to test

if the 3rd value of each array is true

and print the 1st value if it is but

it is printing all values even if wrong ************************************/ if(questionsAnswers[y][2]==true);
{print(questionsAnswers[y][2]+'<br><br>')} }

Steven Parker
Steven Parker
224,848 Points
Steven Parker
Steven Parker
224,848 Points

When posting code, please use the instructions for code formatting in the Markdown Cheatsheet pop-up below the "Add an Answer" area. :arrow_heading_down:

1 Answer

andren
andren
28,550 Points
andren
andren
28,550 Points

This if statement runs regardless of the conditions due to the semicolon you have placed in its declaration. Once JavaScript encounters the semicolon it considers the if statement to be finished. And will therefore treat the rest of the code as being completely independent of the if statement.

If you remove it like this

if(questionsAnswers[y][2]) { // removed ; that came after parenthesis
    print(questionsAnswers[y][2]+'<br><br>')
}

Then your if statement should work the way you want it to.

I also removed the == true part of the condition since it is unnecessary. questionsAnswers[y][2] will either be true or false on its own, so you don't need to compare it with anything.