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# 3.1 name 和 id 和 class
## 標籤名稱
**`$("p")`**：找到標籤名稱為 p 的元素。
**`$("h1")`**：找到標籤名稱為 h1 的元素。
## id
**`$("#my_id")`**：**#** 表示的是 id，即找到 id 為 my\_id 的元素。
**`$("h1#my_title")`**：找到 h1 標籤，且 id 為 my\_title 的元素。
## class
**`$(".my_style")`**：**.** 表示的是 class，即找到 class 為 my\_style 的元素。
**`$("p.my_style")`**：找到 p 標籤，且 class 為 my\_style 的元素。
## 練習
請先建立 `practice/selectors.html` 檔案，用於練習，內容如下：
```markup
jQuery 相關練習
這是標題
這是我的標題
這是段落1
這是段落2
段是段落3
```
試著輸入以下例子，看是否有效：
```javascript
$("h1").css("color", "red");
```
```javascript
$("p").css("color", "red");
```
```javascript
$("h1#my_title").css("color", "red");
```
```javascript
$(".para").css("color", "red");
```
```javascript
$(".para2").css("color", "red");
```
```javascript
$("p.para3").css("color", "red");
```
---
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