如何检查js上的输入字段并根据文本值编写和回答

Question

im new to Javascript and still learning so sorry for the noob question. I want to write a chatbot but I am stuck at the very basic beginning. This is what I wrote so far:

var btt = document.getElementsByClassName(bt);
        var a = document.getElementById("A").textObject.value;
        var b = document.getElementById("B").textObject.value;
        
        var msg = ["Hi", "Hey", "Hello"]

        function one() {
            if (a.value = "Hi") {
             document.getElementById("B").value = "Hello";
          }
        };

I have two input fields and a button. I am trying to get it to check the text value of the first input field (a) by pressing the button (btt) and replying with an answer text (b) based on that text input. I just can't figure out why it does'nt work.

And this is what the html body looks like:

<div align="center" id="A">
            <input type="text" width="250px" height="150"
            placeholder="..." autocomplete="off">
        </div>
        <br>
          <button class="bt" onclick="one()" value="msg">Click me</button>
        <br>
        <br>
        <div align="center" id="B">
          <input type="text" width="250px" height="150"
            placeholder="..." autocomplete="off">
        </div>

Answer 1

You have defined the ids on the wrong element, it should be on input fields.

Few mistakes I have noticed in your code.

1. Ids are defined on the div elements, it should be in input
2. document.getElementsByClassName(bt) bt is a string and it should be wrap with quotes.
3. document.getElementById("A") returns the input object, you don't need to add textObject.value
4. In the if condition you are using single = it should be double == for value comparison or triple === for value and type comparison.

Try this.

 var btt = document.getElementsByClassName("bt"); var a = document.getElementById("A"); var b = document.getElementById("B"); var msg = ["Hi", "Hey", "Hello"] function one() { if (a.value === "Hi") { document.getElementById("B").value = "Hello"; } };

 <div align="center"> <input type="text" id="A" width="250px" height="150" placeholder="..." autocomplete="off"> </div> <br> <button class="bt" onclick="one()" value="msg">Click me</button> <br> <br> <div align="center"> <input type="text" id="B" width="250px" height="150" placeholder="..." autocomplete="off"> </div>