Codecademy javascript 第 7/9 课错误

Question

我已经在 7/9 呆了 2 晚了。这是一款石头剪刀布游戏。我不知道出了什么问题。我尝试了在线 lint，它还说我的第 22 行是一个错误（预期是一个标识符，但却看到了 'else'）。按照说明，我在比较函数内的现有代码下写了另一个 else。

我的代码：

var userChoice = prompt("Do you choose rock, paper or scissors?");
var computerChoice = Math.random();
if (computerChoice < 0.34) {
computerChoice ="rock"
} else if(computerChoice <= 0.67) {
computerChoice ="paper";
} else {
    computerChoice ="scissors";
} console.log("Computer: " + computerChoice);
var compare=function(choice1, choice2){
if(choice1 === choice2) {
    return("The result is a tie!");
}
else if(choice1 ==="rock"){
    if(choice2 ==="scissors")
    return("rock wins");
}
else{
    return"paper wins";
}
    else if(choice1 ==="paper");{
    if(choice2 ==="rock")
    return("paper wins");
}
else{
    return"scissors wins";
}
}

Answer 1

 else if(choice1 ==="paper");{
    if(choice2 ==="rock")
    return("paper wins");
 }

你在 ;

条件之后终止你 else if

应该是：

else if(choice1 ==="paper"){
        if(choice2 ==="rock")
        return("paper wins");
}

Answer 2

var userChoice = prompt("Do you choose rock, paper or scissors?");
var computerChoice = Math.random();
if (computerChoice < 0.34) {
computerChoice ="rock"
} else if(computerChoice <= 0.67) {
computerChoice ="paper";
} else {
    computerChoice ="scissors";
} console.log("Computer: " + computerChoice);
var compare=function(choice1, choice2){
if(choice1 === choice2) {
    return("The result is a tie!");
}
else if(choice1 ==="rock"){
    if(choice2 ==="scissors")
    return("rock wins");
}
else{
    return"paper wins";
}
    else if(choice1 ==="paper");{ -- on this there is semicolon after elseif block.. and how come else if is there after else block.. 
    if(choice2 ==="rock")
    return("paper wins");
}
else{
    return"scissors wins";
}
}

Answer 3

我假设你是初学者。编写非常干净的代码，注意空格和制表符，这是解决调试问题的最佳方法。第22行确实有问题，你在条件语句后面加了一个分号。

var userChoice = prompt("Do you choose rock, paper or scissors?");
var computerChoice = Math.random();
if(computerChoice < 0.34) {
    computerChoice = "rock"
} else if(computerChoice <= 0.67) {
    computerChoice = "paper";
} else {
    computerChoice = "scissors";
}
console.log("Computer: " + computerChoice);
var compare = function(choice1, choice2) {
    if(choice1 === choice2) {
        return("The result is a tie!");
    } else if(choice1 === "rock") {
        if(choice2 === "scissors")
            return("rock wins");
    } else {
        return "paper wins";
    } else if(choice1 === "paper"){//here the error was.
        if(choice2 === "rock")
            return("paper wins");
    } else {
        return "scissors wins";
    }
}

Answer 4

我发现您的代码中存在多个语法错误。它应该如下所示：

var userChoice = prompt("Do you choose rock, paper or scissors?");
var computerChoice = Math.random();

if (computerChoice < 0.34) {
  computerChoice = "rock";
} else if(computerChoice <= 0.67) {
  computerChoice = "paper";
} else {
  computerChoice = "scissors";
} 

console.log("Computer: " + computerChoice);

var compare = function(choice1, choice2) {
  if(choice1 === choice2) {
    return("The result is a tie!");
  } else if(choice1 === "rock") {
    if(choice2 === "scissors") {
      return("rock wins");
    } else {
      return "paper wins";
    }
  } else if(choice1 ==="paper") {
    if(choice2 ==="rock") {
      return("paper wins");
    } else {
      return"scissors wins";
    }
  }
}

Answer 5

您不能在 else 语句后添加 else if，这就是导致您显示错误消息的原因 error(Expected an identifier and instead saw 'else') 当然，在行真正结束之前没有分号

https://jsfiddle.net/8hcpfnhw/

var userChoice = prompt("Do you choose rock, paper or scissors?");
var computerChoice = Math.random();
if (computerChoice < 0.34) {
computerChoice ="rock"
} else if(computerChoice <= 0.67) {
computerChoice ="paper";
} else {
    computerChoice ="scissors";
} console.log("Computer: " + computerChoice);

var compare=function(choice1, choice2){
if(choice1 === choice2) {
    return("The result is a tie!");
}
else if(choice1 ==="rock"){
    if(choice2 ==="scissors")
    return("rock wins");
}
else if(choice1 === "paper"){ // I changed this to else if instead of else
    return "paper wins";
}
else if(choice1 ==="paper") {
    if(choice2 ==="rock")
return("paper wins");
}
else{ // only else as last check
    return"scissors wins";
}
}

Codecademy javascript 第 7/9 课错误

Codecademy javascript lesson 7/9 error

javascript

syntax-error