JavaScript 自动更改 img src

Question

问题

我的项目几乎完成了，但我还有一个问题我想不通。我需要在提示框关闭时自动更改图像src。这就是我的意思。

示例

假设我有这个代码。

HTML

<button id="begin" onClick="javascript:fight();">Begin</button>
<img id="scenario" src="http://www.thegaminghideout.com/school/stage1.png">

JAVASCRIPT

function fight()  {
  var img = document.getElementById("scenario");
  var start = document.getElementById("begin");
  img.src = "http://www.thegaminghideout.com/school/map.jpg"; /* This changes it when the function is called */
  var decision1 = function()  {
    var decision = prompt("What do you do now? ATTACK, SLEEP, or PASS?").toUpperCase();
    if(decision === "ATTACK")  {
      attack();
    }
    if(decision === "SLEEP")  {
      sleep();
    }
    if(decision === "PASS")  {
      skip();
    }
  }

问题

当提示对话框关闭时，如何自动更改 img 的 src？或者，检查它是否打开？

我尝试了什么

• 将img.src = "http://www.thegaminghideout.com/school/stage1.png"; 放在后面 fight()函数
• 尝试这样的检查：if(fight() === true) { img.src =
"http://www.thegaminghideout.com/school/stage1.png"; }
• 添加“刷新”功能，但会破坏代码。

注意事项

• 我知道我在示例中的 JavaScript 可能看起来是错误的， 因为我语法错误或者没有attack()、sleep()，或者 skip() 函数。好吧，这只是一个例子，所以我不发布 我的整个游戏代码在这里，大约 1000 行。
• 我将使用上面提供的代码和 JSFiddle 发布一个 sn-p 与带有完整代码的实际项目一起更好 疑难解答。

function fight() {
  var img = document.getElementById("scenario");
  var start = document.getElementById("begin");
  img.src = "http://www.thegaminghideout.com/school/map.jpg"; /* This changes it when the function is called */
  decision1();
  var decision1 = function() {
    var decision = prompt("What do you do now? ATTACK, SLEEP, or PASS?").toUpperCase();
    if (decision === "ATTACK") {
      attack();
    }
    if (decision === "SLEEP") {
      sleep();
    }
    if (decision === "PASS") {
      skip();
    }
  }
}

<img id="scenario" src="http://www.thegaminghideout.com/school/stage1.png">
<button id="begin" onClick="javascript:fight();">Test</button>

http://jsfiddle.net/d8sxxykj/

Answer 1

function fight()  {

  var start = document.getElementById("begin");
  var decision1 = function()  {
    var img = document.getElementById("scenario");
    var decision = prompt("What do you do now? ATTACK, SLEEP, or PASS?").toUpperCase();
    if(decision === "ATTACK")  {
    img.src = "http://www.thegaminghideout.com/school/map.jpg";
    attack();
    }
    if(decision === "SLEEP")  {
    img.src = "something.jpg";
    sleep();
    }
    if(decision === "PASS")  {
    img.src = "something.jpg";
    skip();
    }
}  

Answer 2

试试，

$("#scenario").attr("src", "http://www.thegaminghideout.com/school/stage1.png");

而不是

img.src = "http://www.thegaminghideout.com/school/stage1.png";

希望对你有帮助！