改變屬性

改變文字顏色

document.getElementById("label").style.color = "red";

改變文字大小

document.getElementById("label").style.fontSize = "36px";

改變文字字型

document.getElementById("label").style.fontFamily = "36px";

關閉按鈕功能

var adminButton = document.getElementById("admin"); //建立按鈕物件

adminButton.disabled = true;

改變圖片連結

var logo = document.getElementById("logo"); //建立img物件

logo.src = "新的連結";

更改input屬性readOnly

來回切換

<input type="text" id="單號" placeholder="新增時自動產生" readonly>

<button onclick="switchID()">單號輸入切換</button>

function switchID(){

  const inputElement = document.getElementById('單號');

  inputElement.readOnly = !inputElement.readOnly;

  if(inputElement.readOnly){

    inputElement.value = "";

  }else{

    inputElement.focus();

  }

}