Question

我现在才开始学习。你能帮帮我吗，为什么我没有得到正确的输出。这是我的代码：

//ask questions
var quiz = [
  ["When is Bulgaria established?", 681],
  ["What year was it before 16 years?", 2000],
  ["When does WWII ends?", 1945]
];

//variables
var answer = [];
var correct = [];
var wrong = [];
var correctAns = 0;
var wrongAns = 0;
var oList = "<ol>";

//function to print the result in ordered list
function printResult(result){
  for(var j = 0; j < result.length; j++){
    oList += "<li>" + result[i] + "</li>";
  }
  oList += "</ol>";
  return oList;
}

function print(message) {
  document.getElementById('output').innerHTML = message;
}



//looping, adding correct and wrong answeres
for(var i = 0; i < 3; i++) {
  answer[i] = prompt(quiz[i][0]);
  if(parseInt(answer[i]) == quiz[i][1]){
    correct.push(quiz[i][0]);
    correctAns++;
  } else {
    wrong.push(quiz[i][0]);
    wrongAns++;
  }
}


//print logic
if(correct.length < 1 || correct == undefined){
  print("You did not guess any of the quiestions!");
} else if (correct.length >= 1){
  print("You have guessed " + correctAns + " questions.");
  print(printResult(correct));
  print("You have " + wrongAns + " wrong answeres.");
  if(wrongAns > 0){
    print(printResult(wrong));
  }
}

我一遍又一遍地看了这段代码，但我仍然无法理解为什么我的结果未定义。在调试器中，在循环之后我检查我的变量，一切似乎都没问题。

Answer 1

在printResult函数中，您使用的是var i而不是j，

另外，您最好使用innerHtml + = message;

//ask questions
var quiz = [
  ["When is Bulgaria established?", 681],
  ["What year was it before 16 years?", 2000],
  ["When does WWII ends?", 1945]
];

//variables
var answer = [];
var correct = [];
var wrong = [];
var correctAns = 0;
var wrongAns = 0;
   

//function to print the result in ordered list
function printResult(result){
//HERE:
 var oList = "<ol>";
  for(var j = 0; j < result.length; j++){
    oList += "<li>" + result[j] + "</li>";
  }
  oList += "</ol>";
  return oList;
}

function print(message) {
  document.getElementById('output').innerHTML += message;
}



//looping, adding correct and wrong answeres
for(var i = 0; i < 3; i++) {
  answer[i] = prompt(quiz[i][0]);
  if(parseInt(answer[i]) == quiz[i][1]){
    correct.push(quiz[i][0]);
    correctAns++;
  } else {
    wrong.push(quiz[i][0]);
    wrongAns++;
  }
}


//print logic
if(correct.length < 1 || correct == undefined){
  print("You did not guess any of the quiestions!");
} else if (correct.length >= 1){
  print("You have guessed " + correctAns + " questions.");
  print(printResult(correct));
  print("You have " + wrongAns + " wrong answeres.");
  if(wrongAns > 0){
    print(printResult(wrong));
  }
}

<div id="output">
</div>

Answer 2

你的主要错误是使用我的j：

for(var j = 0; j < result.length; j++){
   oList += "<li>" + result[j] + "</li>";// here was i before
}

Answer 3

基本上你有三个问题。

重用oList，该变量应在声明内部并仅在printResult中使用。
在printResult内，使用已使用i的{{1}}
在j，您可以使用新内容替换实际内容。

只是一个小变量，带有用于计数的变量名称。最好始终使用print而不是i开始，然后继续使用字母表中的字母。

＆＃13;

简单的测验游戏JavaScript

3 个答案: