Course Introduction：In web development, creating drop-down lists using HTML5 mainly depends on select and option tags. 1. Basic structure: define options by defining the drop-down box; 2. Add default selections: Use selected attribute to set the default options; 3. Group display options: use the classification of options; 4. Optional advanced functions: realize multiple selection through multiple, and control the number of display options through size. These tips can improve form clarity and user experience.
2025-07-19 comment 0 508
Course Introduction：To create an HTML drop-down list, you need to use and tags, which define the drop-down box and define options; 1. Use the associated drop-down list to improve accessibility; 2. Set the default options through the selected attribute; 3. Use logical grouping of options; 4. Set the name attribute for data identification when submitting the form, and the value attribute defines the submitted value; 5. You can add the required attribute to force selection, or use the multiple attribute to allow multiple selections to finally implement a simple and well-compatible drop-down list.
2025-08-01 comment 0 420
Course Introduction：To create an HTML form, there are 5 main tags, namely,,,, and. 1. It is a form container, responsible for organizing and submitting data. Common properties include action, method and enctype; 2. Define multiple input types such as text, password, email, radio, checkbox and submit through type attributes; 3. Used to enter multiple text lines; 4. Used to create a drop-down selection menu in conjunction with creating a drop-down selection menu; 5. Used to submit or trigger interactive behavior, and combine it to improve accessibility and user experience. Master these tags and corresponding attributes to build a complete web form.
2025-07-01 comment 0 938
Course Introduction：VS Code To switch Chinese mode: Open the settings interface (Windows/Linux: Ctrl, macOS: Cmd,) Search for "Editor: Language" settings Select "Chinese" in the drop-down menu Save settings and restart VS Code
2025-04-15 comment 0 805
Course Introduction：To implement the multiple selection function of HTML drop-down list, you need to use the multiple attribute, 1. Add the multiple attribute to the select tag to enable multiple selection; 2. You can set the size attribute to specify the number of visible rows to improve usability; 3. Note that native multiple selection is not good on touch screen devices, and you can consider using check boxes or modern components instead; 4. When submitting the form, the parameters of the same name will be sent repeatedly, and the backend needs to support multi-value processing, such as PHP requires the name="field[]" syntax; 5. The selected value array can be obtained through the selected Options attribute of JavaScript. Correctly configure the front and back ends and user experience details to complete the multi-select function.
2025-08-02 comment 0 214
Course Elementary 13817
Course Introduction：Scala Tutorial Scala is a multi-paradigm programming language, designed to integrate various features of object-oriented programming and functional programming.
Course Elementary 82350
Course Introduction："CSS Online Manual" is the official CSS online reference manual. This CSS online development manual contains various CSS properties, definitions, usage methods, example operations, etc. It is an indispensable online query manual for WEB programming learners and developers! CSS: Cascading Style Sheets (English full name: Cascading Style Sheets) is an application used to express HTML (Standard Universal Markup Language).
Course Elementary 13173
Course Introduction：SVG is a markup language for vector graphics in HTML5. It maintains powerful drawing capabilities and at the same time has a very high-end interface to operate graphics by directly operating Dom nodes. This "SVG Tutorial" is intended to allow students to master the SVG language and some of its corresponding APIs, combined with the knowledge of 2D drawing, so that students can render and control complex graphics on the page.
Course Elementary 24624
Course Introduction：In the "AngularJS Chinese Reference Manual", AngularJS extends HTML with new attributes and expressions. AngularJS can build a single page application (SPAs: Single Page Applications). AngularJS is very easy to learn.
Course Elementary 27482
Course Introduction：Go is a new language, a concurrent, garbage-collected, fast-compiled language. It can compile a large Go program in a few seconds on a single computer. Go provides a model for software construction that makes dependency analysis easier and avoids most C-style include files and library headers. Go is a statically typed language, and its type system has no hierarchy. Therefore users do not need to spend time defining relationships between types, which feels more lightweight than typical object-oriented languages. Go is a completely garbage-collected language and provides basic support for concurrent execution and communication. By its design, Go is intended to provide a method for constructing system software on multi-core machines.
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