Question

基本上，我使用bootstrap作为我的CSS，但我遇到了一个问题。当我点击按钮（id="myQuestionButton"）时，我希望它从输入框（id="myInput"）获取输入并通过function checkQuestionWords()运行。

以下是与输入和按钮有关的代码块：

<div class="input-append span9 offset3">
  <form>
    <input class="span4" type="text" id="myInput" 
    placeholder="Enter your question."></input>
    <button class="btn" type="submit" id="myQuestionButton">
    Let's check second.</button>
  </form>
</div>

以下是打印初步结果的位置（目前仅在<div> </div>中）：

<div id="results"></div>

到目前为止，这是我的功能：

function checkQuestionWords(){
  var theInput = document.getByElementId("myInput");
  var theQuestion = theInput.trim();
  var questionWords = ["who", "what", "where", "when", "why", "how"];
  var isItGood = false;

for (var i=0, i<7; i++){
  var holder1 = questionWords[i];
  var holder2 = holder1.length;
    if (theQuestion.substr(0,holder2) == questionWords[i]){
      isItGood = true;
      break;}
    else{
      isItGood = false;}}

if (isItGood == false){
  document.getByElementId("results") = "Please enter a question...";}
  //the above just reminds them to begin with a question word; see questionWords
else{
  document.getByElementId("results") = "all is good";}

}

我尝试在onclick=checkQuestionWords()"内部执行整个<button ...></button>但由于某种原因无效。

Answer 1

你问题就在于你正在使用 var theInput = document.getByElementId("myInput");？

这将为您提供输入控件，其中id为 myInput ，但不包含其中的文本。你想要更像

的东西

var theInput = document.getByElementId("myInput").value;

这将为您提供实际文本，然后您可以使用

将其分配给theQuestion

var theQuestion = theInput.trim();

Answer 2

尝试这样的简单调用：

var btn = document.getElementById["myQuestionButton"];
btn.onClick = checkQuestionWords;

Answer 3

上述代码中存在许多问题：

问题是：

getByElementId应为getElementById
document.getByElementId("myInput")应为document.getElementById("myInput").value;
document.getByElementId("results")应为document.getElementById("results").innerHTML

请参阅下面的工作代码：

<script>
function checkQuestionWords() {
    var theInput = document.getElementById("myInput").value;
    var theQuestion = theInput;//.trim();
    var questionWords = ["who", "what", "where", "when", "why", "how"];
    var isItGood = false;


    for (var i=0; i<7; i++){
      var holder1 = questionWords[i];
      var holder2 = holder1.length;
        if (theQuestion.substr(0,holder2) == questionWords[i]){
          isItGood = true;
          break;}
        else{
          isItGood = false;}}

    if (isItGood == false){
      document.getElementById("results").innerHTML = "Please enter a question...";
    }
      //the above just reminds them to begin with a question word; see questionWords
    else{
      document.getElementById("results").innerHTML = "all is good";
    }

    return false;

}
</script>
<div class="input-append span9 offset3">

    <input class="span4" type="text" id="myInput" 
    placeholder="Enter your question."></input>
    <button class="btn" type="submit" id="myQuestionButton" onclick="checkQuestionWords();">
Let's check second.</button>

</div>
<div id="results"></div>

当我点击一个按钮（使用bootstrap）时需要通过一个函数运行<input />

3 个答案: