Question

我的代码有问题，我想在历史记录框中看到通过的4个生成的数字（Math.random），但这些数字显示的相同。有没有办法延迟var？

我尝试按顺序排列var，但这不会造成延迟。

我的html：

    <div class="text-position-history">
        <div class="text-style-history">
            <p id="historyT"></p>
        </div>
    </div>

</body>

</html>

我的JavaScript：

var green = 0;
var red = 0;

function odds(){

    var result = Math.random();

    if (result < 0.5)
    {
        document.body.style.backgroundColor = "green";
        green++;
        document.getElementById('greenT').innerHTML = "Times you survived: " + " " + green;

    }
    else{
        document.body.style.backgroundColor = "red";
        red++;
        document.getElementById('redT').innerHTML = "Times you died: " + " " + red;
    }

    document.getElementById('resultT').innerHTML = "Guessed number: " + " " + result;

    var history1 = result;
    var history2 = history1;
    var history3 = history2;

    document.getElementById('historyT').innerHTML = "Guessed number: " + " " + result + " " + history1 + " " + history2 + " " + history3;


}

有没有办法做到这一点？

Answer 1

为什么不创建一个数组，然后在调用Math.random()之后将结果的新值附加到该数组？

var resultHistory = new Array();

var result = Math.random();
resultHistory.push(result);

然后稍后打印出阵列。

Answer 2

为什么不只使用数字数组？

const bus = require("./bus");

class Subscriber {
    constructor(emitter) {
        this.emitter = emitter;
        console.log(this.emitter);

        this.emitter.on("test", this.handleTest);
    }

    handleTest(data) {
        console.log("handling test", data);
    }
}

module.exports = Subscriber;

console.log(bus.instance.foo);

var _history = [];

function toHTMLElement(historyNode)
{
  var node = document.createElement("div");
  node.innerHTML = historyNode.text;
  node.style.background = historyNode.win?'green':'red';
  return node;
}

function renderHistory()
{
  var result = document.getElementById("result");
  result.innerHTML = "";
  _history.forEach(function(e){
    result.appendChild(toHTMLElement(e));
  });
}

document.getElementById("form").addEventListener("submit", function(e){
  e.preventDefault();
  
  _history.push((Math.random()>0.5)?{win: true, text: 'You win'}:{win: false, text: 'You lose'});
  if (_history.length > 3) _history.shift();
  renderHistory();
});

Answer 3

var green = 0;
var red = 0;

function odds(){

    var result = Math.random();

    if (result < 0.5)
    {
        document.body.style.backgroundColor = "green";
        green++;
        document.getElementById('greenT').innerHTML = "Times you survived: " + " " + green;

    }
    else{
        document.body.style.backgroundColor = "red";
        red++;
        document.getElementById('redT').innerHTML = "Times you died: " + " " + red;
    }

    document.getElementById('resultT').innerHTML = "Guessed number: " + " " + result;

    var myList = [result, result, result];

    var history1 = myList.shift();

    var history2 = myList.shift();

    var history3 = myList.shift();

    document.getElementById('historyT').innerHTML = "Guessed numbesr: " + " " + history1 + " " + history2 + " " + history3;

}

这仍然给出相同的结果吗？

Answer 4

我认为实际上更改历史记录变量的顺序应该可以解决。将它们更改为

    var history3 = history2;
    var history2 = history1;
  var history1 = result;

现在，您对所有结果都一无所知，原因是：

var history1 =结果 var history2 = history1（history1现在已指向结果）

如何创建我的var的历史记录（Math.random）

4 个答案: