使用javascript中的功能更改目标文本框的值

Question

I want to create a function to change the value of targeting textbox but I can't figure out what's wrong with my code.

<form name="formcalc">
  <input type="text" value="1" name="A" >
  <input type="button" value="Change" onClick="change(A)">
  <br>
  <input type="text" value="2" name="B" >
  <input type="button" value="Change" onClick="change(B)">
</form>
<script>
function change(x) {
       document.formcalc.x.value = 3;
}
</script>

Answer 1

As you are sending the element directly to the function, below will work

function change(x) {
   x.value = 3;
}

Answer 2

尝试在输入type = text中添加id属性，并使用进行调用

document.getElementById("nameId").innerHTML=yourdata...