How to create a linked deletion system using JavaScript-Front-end Q&A-php.cn

How to create a linked deletion system using JavaScript

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Release： 2023-04-19 14:47:24

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In web development, JavaScript is widely used along with HTML and CSS to create interactive and dynamic web pages. One of the common requirements is to achieve linkage effects between different elements in web pages. This article will introduce how to use JavaScript to create a linked deletion system so that when one element is deleted, another related element will also be deleted.

First of all, we need to understand the implementation principle of this system. On a Web page, different elements can be selected and controlled by their ID or class name. We will use JavaScript's DOM (Document Object Model) manipulation to detect and remove elements. Specifically, we will use the following method:

Select the element to monitor. In our example we will use a checkbox and a list. When the checkbox is checked, we will remove all elements in the list that are related to the selected item.
Add event listener. Add a "click" event listener for the checkbox. When the check box status changes, the listener will start the linkage deletion system.
Check the target element. Each list element is checked to determine whether it is related to the specified option. If a list element has a specific class, i.e. the same value as the option, then the element should be removed.
Delete the target element. Once we have identified the element we want to remove, we will use the remove() method in JavaScript to remove it from the document.

The following is a simple example showing how to use JavaScript to create a linked deletion system. In this example we have a checkbox and a list with two items. When a checkbox is selected, all items in the list with the same class as the selected checkbox will be deleted.

<!DOCTYPE html>
<html>
<head>
   <title>JavaScript联动删除示例</title>
   <script type="text/javascript">
       function deleteItem() {
           var checkBox = document.getElementById("check1");
           var listItems = document.getElementsByTagName("li");
           for(var i = 0; i < listItems.length; i++) {
               if(listItems[i].className === checkBox.className) {
                   listItems[i].remove();
               }
           }
       }
   </script>
</head>
<body>
   <label for="check1">选项1</label>
   <input type="checkbox" id="check1" class="option1" onclick="deleteItem()"/>
   <br><br>
   <ul>
       <li class="option1">选项1，需要删除</li>
       <li class="option2">选项2，不需要删除</li>
       <li class="option1">选项1，需要删除</li>
   </ul>
</body>
</html>

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In the above example, we first define a checkbox element with an ID and class, and add a "click" event listener to it. Then, we define a function deleteItem() to iterate through all list items and delete the options that match the checkbox's class. Finally, we associate this function with the checkbox's event listener.

When the check box is selected, the deleteItem() function will be called to start checking all list items. If the list item's class is the same as the checkbox's class, the list item will be removed.

It should be noted that this example is for demonstration purposes only. In actual web development, you may need more complex code to handle different types of elements and deletion operations.

Summary

JavaScript provides a flexible method to achieve linkage effects between different elements. By using DOM operations and event listeners, we can easily create a variety of interactive effects, including a linked deletion system. When writing JavaScript code, be sure to be accurate and safe. Proper use of the language can provide your web application with better user experience and functionality.

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