图片不会因为修改而改变"src"

Question

好吧，我正在尝试编写另一个程序来练习我的 Javascript，但我遇到了另一个障碍。现在，程序很简单。 Select 来自种族列表的下拉列表（目前仅限于 "Swede" 和 "Italian"），然后程序将写下他们（刻板印象）外貌的简短描述，以及post 一张图片。或者更确切地说，更改默认 "Mystery man" 图片。

第一部分工作正常。文本会根据您 select "Swede" 或 "Italian." 而变化，图片部分不会。图片不会更改其默认 "Mystery man" 图片。这是为什么？

var ethnicities = [{
    name: "Swede",
    eyecolor: "blue",
    hairtex: "straight",
    fp: 1,
    pic: "Swedish.png"
  },
  {
    name: "Italian",
    eyecolor: "brown",
    hairtex: "curly",
    fp: 2,
    pic: "Italian.png"
  }
];


function description() {
  var desc = "The " + ethnicities[document.EPF.EPDD.value].name +
    " is " + ethnicities[document.EPF.EPDD.value].eyecolor + "-eyed and " +
    ethnicities[document.EPF.EPDD.value].hairtex + "-haired." +
    "";



  document.getElementById("demo").innerHTML = desc;
  document.getElementbyId("picture").src = ethnicities[document.EPF.EPDD.value].pic;
  //so weird, it just doesn't chnage it.  It doesn't matter what I put on the
  //right of the equal sign.
}

<p>Ethnicity presets:</p>
<form name="EPF">
  <select name="EPDD">
    <option value="0">Swede</option>
    <option value="1">Italian</option>
   
    </select>

  <input type="button" value="Submit" onClick="description()">

</form>
<p id="demo"> </p>

<img id="picture" src="Mystery man.png" alt="unknown">

Answer 1

document.getElementbyId("picture").src = ethnicities[documen...

应该是

document.getElementById("picture").src = ethnicities[documen...

您忘记在 'elementById'

中将 'b' 大写

Answer 2

这只是一个语法错误，不要忘记始终查看控制台以检测 problem.You 只需在“document.getElementById()”中写入大写 "B" 即可。

图片不会因为修改而改变"src"

Picture won't change by modifying "src"

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