问使用onclick函数更改按钮值

EN

<script>
function changeValue(button) {
  console.log('The original value of the button is: ', button.value, ' and the innerHTML is: ', button.innerHTML);
  if (button.value == "UTC") {
    button.value = "Local time";
    console.log('Now the value has changed to: ', button.value, ' but the innerHTML has not: ', button.innerHTML);
    button.innerHTML = "Local time";
    console.log('The new value of the button is still: ', button.value, ' but now the innerHTML is also changed: ', button.innerHTML);
  } 
}

<button id="tz" type="button" value="UTC" onClick="changeValue(this);" name="button">UTC</button>  

var btn = document.getElementById("tz");

function button() {
  if (btn.value == "UTC") {
    btn.value = "Local time";
  } else {
    btn.value = "UTC";
  }
}

btn.addEventListener("click", button, false);

<input type="button" id="tz" value="UTC"></input>