Copy code The code is as follows:<select> <option value="">1</option> <option value="">2</option> <option value="">3</option> <option value="">4</option> <option value="">5</option> </select> ![]() I don't want users to be able to choose 345. What should I do? Copy code The code is as follows:<select> <option value="">1</option> <option value="">2</option> <optgroup label="3"></optgroup> <optgroup label="4"></optgroup> <optgroup label="5"></optgroup> </select> ![]() That's it. |
<<: MySQL configuration master-slave server (one master and multiple slaves)
>>: Why is the scroll bar on the web page set on the right?
The detailed process of installing python3.7.0 on...
First, I will give you the VMware 14 activation c...
Use the for loop to import the zabbix image into ...
1. Download MySQL 1.1 Download address https://do...
Today's screen resolutions range from as smal...
Table of contents nonsense Functions implemented ...
Before configuration, we need to do the following...
Phenomenon Start the Docker container docker run ...
background Indexes are a double-edged sword. Whil...
This article example shares the specific code of ...
The <label> tag defines a label (tag) for an...
Today I want to summarize several very useful HTML...
There is currently a requirement that an operatio...
Table of contents What is JSON Why this technolog...
Pseudo-elements and pseudo-classes Speaking of th...