javascript - 如何检测在javascript中单击了哪个按钮？

Question

我正在尝试弄清楚如何在单击我的函数时携带按钮的 ID。 1 个函数在鼠标悬停时更改颜色，一个函数在鼠标移开时将其更改回原始颜色。我知道我可以在 css 中简单地做到这一点，但我只想学习如何在 javascript 中做到这一点。提前致谢。下面是我的代码。

  var buttonClass = this.className();
 // document.getElementById("mainTitle");
  this.style.backgroundColor="#000000";
  this.style.color="#ffffff";
  this.style.cursor = "pointer";  
}

function defaultColor() {
  var buttonClasss = this.getElementById();
  //document.getElementById("addList");
  this.style.backgroundColor = "#ffffff";
  this.style.color = "#000000";
    this.style.cursor = "pointer";
}
  

//event listener for Change Title button
document.getElementById("mainTitle").addEventListener("mouseover", changeColor);
document.getElementById("mainTitle").addEventListener("mouseout", defaultColor);
document.getElementById("mainTitle").addEventListener("click", changeTitle);
//event listener for change title ends here

//event listener for add listing
document.getElementById("addList").addEventListener("mouseover", changeColor);
document.getElementById("addList").addEventListener("mouseout", defaultColor);
document.getElementById("addList").addEventListener("click", addListing);
//event listener for add listing ends here

#mainTitle {
  border:1px solid #ff33f4;
  float:left;
  clear:both;
  font-family:arial;
  font-weight:bold;
  font-size:20px;
  border-radius:50px;
  background-color:#ff33ff;
  width:200px;
  height:35px;
  text-align:center;
  padding-top:20px;
  padding-bottom:10px;
  cursor:pointer;
}

#addList {
  border:1px solid #ff33f4;
  float:right;
  font-family:arial;
  font-weight:bold;
  font-size:20px;
  border-radius:50px;
  background-color:#ff33ff;
  width:200px;
  height:35px;
  text-align:center;
  padding-top:20px;
  padding-bottom:10px;
  cursor:pointer;
}

#main {
  clear:both;
  margin-top:120px;
}

 
  <div id="mainTitle" class="changeTitle">Change Title</div>
  <div id="addList" class="addList">Add List</div>

Answer 1

每个注册的事件都会带有参数 Event .

function defaultColor(e) {
                  //  ^ argument (Event)

     var currentClickedButton = e.currentTarget;   // to get the current clicked button
     /* Your code here */
}