Can a function be used to redirect?-CodePudding

so I have a developing a trivia game and I have am trying to have a function redirect to a page that tells them if the answer was correct or not. Below shows what I have going on.

My functions to check the answers that the end user inputed.

function Question(stem, answer, type){
    this.stem = stem; 
    this.answer = new Array(rowLimit);
    this.answer.push(answer);
    this.type = type;
}
function score(userAnswer){
    var result = "";
    console.log("Data returning for this.answer: "   this.answer);
    var lowerUserAnswer = userAnswer.toLowerCase().trim();

    for(var a = 2;  a < this.answer.length; a  ){
        lowerAnswer = this.answer[a].trim().toLowerCase();
      
        if (type == 1) { // this is a true / false question
            console.log('Inside type 1');
            result = trueFalseResponses(lowerUserAnswer, lowerAnswer);
        } else if (type == 2) {// single word question
            console.log('Inside type 2');
            result = singleWordResponses(lowerUserAnswer, lowerAnswer);
        } else if (type == 3){ // sentence question
            console.log('Inside type 3');
            result = sentenceResponses(lowerUserAnswer, lowerAnswer);
        } else {
            console.log('Inside of else');
            console.log("Question type is needed.");
        }
        return result;
    }
}
function trueFalseResponses(userInput, realAnswer){
   if(userInput.charAt(0) == realAnswer.charAt(0)) {
        console.log('Inside of if trueFalseResponses');
        correctAnswerIncrease();
    }
   else {
        console.log('Inside of else trueFalseResponses');
        incorrectAnswerIncrease();
    }
   return "";
}
function singleWordResponses(userInput, realAnswer){
   if(userInput === realAnswer) {
        console.log('Inside of if singleWordResponses');
        correctAnswerIncrease();
   }
   else {
        console.log('Inside of else singleWordResponses');
        incorrectAnswerIncrease();
   }
   return "";
}
function sentenceResponses(userInput, realAnswer){
   if(userInput.includes(realAnswer)) {
        console.log('Inside of if sentenceResponses');
        correctAnswerIncrease();
   }
   else {
        console.log('Inside of else sentenceResponses');
        incorrectAnswerIncrease();
   }
   return "";
}
function correctAnswerIncrease (req, res, next){
    console.log('Inside of if correctAnswerIncrease');
    incremented = incremented   1;
    soulTracker = soulTracker   1;
    res.redirect('/correct');
}
function incorrectAnswerIncrease(req, res, next){
    console.log('Inside of if incorrectAnswerIncrease');
    res.send('/incorrect');
    incremented = incremented   1;

Web pages that tells them if the response was correct or not...

app.get('/correct', (req, res, next) => {
    res.render('correct');
});
app.get('/incorrect', (req, res, next) => {
    res.render('incorrect');
});
app.post('/correct', (req, res, next) => {
    res.render('correct');
});
app.post('/incorrect', (req, res, next) => {
    res.render('incorrect');
});

So when the answer is inputed, depending on the type of response the question can take, it's passed from score, to the question type which is either trueFalseResponses, singleWordResponses, or sentenceResponses. If the response was correct, or incorrect, I want the page to redirect them to /correct or /incorrect. However, when I attempted that, I received the following error.

TypeError: Cannot read properties of undefined (reading 'redirect')

I have tried to use window.location.href, window.location.href and window.location.replace but that has not helped as well. The goal is to redirect them to /correct or /incorrect if the response from the user was correct or incorrect.

CodePudding user response：

In this code:

function sentenceResponses(userInput, realAnswer){
   if(userInput.includes(realAnswer)) {
        console.log('Inside of if sentenceResponses');
        correctAnswerIncrease();
   }
   else {
        console.log('Inside of else sentenceResponses');
        incorrectAnswerIncrease();
   }
   return "";
}

You call either correctAnswerIncrease() or incorrectAnswerIncrease(), but those two functions expect multiple parameters to be passed to them:

function correctAnswerIncrease (req, res, next){
    console.log('Inside of if correctAnswerIncrease');
    incremented = incremented   1;
    soulTracker = soulTracker   1;
    res.redirect('/correct');
}
function incorrectAnswerIncrease(req, res, next){
    console.log('Inside of if incorrectAnswerIncrease');
    res.send('/incorrect');
    incremented = incremented   1;
}

Thus, when you try to use res inside those functions, you get an error because the caller didn't pass res and thus they are undefined. When you call a function, you MUST pass the arguments that the function expects.

In addition incorrectAnswerIncrease() probably should be res.redirect('/incorrect'), not res.send('/incorrect').

I might also mention that it appears you're using server-wide variables here like incremented and soulTracker. That will work only if all users are supposed to share the same variables. If these are supposed to be user-specific variables, this will not work as all users will be sharing the same variables.

CodePudding user response：

I ended up restructuring the code by making the following changes.

The codes below became booleans.

function score(userAnswer){
var result = "";
console.log("Data returning for this.answer: "   this.answer);
var lowerUserAnswer = userAnswer.toLowerCase().trim();

for(var a = 2;  a < this.answer.length; a  ){
    lowerAnswer = this.answer[a].trim().toLowerCase();
  
    if (type == 1) { // this is a true / false question
        console.log('Inside type 1');
        result = trueFalseResponses(lowerUserAnswer, lowerAnswer);
    } else if (type == 2) {// single word question
        console.log('Inside type 2');
        result = singleWordResponses(lowerUserAnswer, lowerAnswer);
    } else if (type == 3){ // sentence question
        console.log('Inside type 3');
        result = sentenceResponses(lowerUserAnswer, lowerAnswer);
    } else {
        console.log('Inside of else');
        console.log("Question type is needed.");
    };
    console.log('Result from score is '   result);
    if (result === true) {
        soulTracker  = 1;
        incremented  = 1;
    } else {
        incremented  = 1;
    };
    return result;
}}

function trueFalseResponses(userInput, realAnswer){
   if(userInput.charAt(0) == realAnswer.charAt(0)) {
        console.log('Inside of if trueFalseResponses');
        return true;
    } else {
        console.log('Inside of else trueFalseResponses');
        return false;
    }}

function singleWordResponses(userInput, realAnswer){
   if(userInput === realAnswer) {
        console.log('Inside of if singleWordResponses');
        return true;
    } else {
        console.log('Inside of else singleWordResponses');
        return false;
    }}

function sentenceResponses(userInput, realAnswer){
   if(userInput.includes(realAnswer)) {
        console.log('Inside of if sentenceResponses');
        return true;
    } else {
        console.log('Inside of else sentenceResponses');
        return false;
    }}

I also made the following changes to my post method.

app.post('/triviaquestions', (req, res, next) => {
if (score(req.body.triviaResponse) === true){
    console.log('Inside of if score = true');
    res.redirect('/correct');
}
else {
    console.log('Inside of if score = false');
    res.redirect('/incorrect');
}});

These changes turned out to be successful.