After following, you can keep track of his dynamic information in a timely manner
The child component passes the value to the parent component through a custom event, triggers the event with $emit and passes data, and listens to the event through v-on in the parent component to receive data. 1. Use this.$emit('event name', data) to send data in the child component; 2. The parent component receives data through @event name="handling function"; 3. It is recommended to use kebab-case to name the event name; 4. It is not recommended to directly modify props to achieve backward transmission; 5. EventBus or Vuex/Pinia can be used for communication when nesting multiple layers. The whole process is clear and flexible, and is suitable for a variety of data transfer scenarios.
Jul 06, 2025 am 01:42 AM
1. Bytes and str should be clearly distinguished. Strings are text data, bytes are binary data, and cannot be spliced ??directly. .encode() and .decode() are required to convert; 2. Add the 'b' pattern to process bytes when reading and writing files, such as 'rb' or 'wb' to avoid parsing errors; 3. The struct module is used to package and unpack structured binary data, pay attention to the matching of byte order and format; 4. Bytearray is more flexible than bytes, suitable for frequent modification of binary content.
Jul 06, 2025 am 01:42 AM
defineExpose is used in Vue3 to explicitly define variables or functions that should be exposed when a component is accessed through ref. In, the contents of internal declarations will not be automatically exposed by default. You must manually specify the items that need to be exposed through defineExpose. For example, to access someData and updateData of a child component through ref in the parent component, you need to use defineExpose({someData, updateData}) for exposure. Its usage is: 1. Define the variables or functions to be exposed in the child component; 2. Call defineExpose and pass in the object containing these items. Applicable scenarios include building reusable components (such as providing .f
Jul 06, 2025 am 01:41 AM
TocheckfreespaceandlargefilesonLinux,usedfandducommands.Rundf-htoviewfreediskspaceinhuman-readableformat,focusingonthe"Avail"column.Forspecificdirectories,addthepathtothecommand.Usedu-sh/path/to/directorytoseediskusagesummaries,anddu-sh*/|s
Jul 06, 2025 am 01:40 AM
In the Vue.js single file component, exportdefault uses exportdefault to declare the component. 1. Components must be exported through exportdefault; 2. The basic structure includes options such as name, data, template; 3. data must be a function that returns responsive data objects; 4. The template is usually written in a separate tag; 5. In Vue3, Composition API or syntax sugar can be used to simplify the code; 6. It is recommended to use PascalCase to name components; 7. Ensure that the build tool can correctly parse .vue files.
Jul 06, 2025 am 01:40 AM
HTML5 tags are used to create reusable lazy content structures. The specific steps are: 1. Define the template; 2. Obtain and clone the template content through JavaScript; 3. Insert the clone content into the page. Its features include default invisible, support for any HTML, and require JS operations. It is suitable for scenarios such as component structure, dynamic loading, and preloading resources. The scripts and styles in the template need to be specially processed and cannot be nested in specific tags.
Jul 06, 2025 am 01:39 AM
Using CSS preprocessors can improve maintainability and clarity of style sheets. 1. Nesting rules make the structure more intuitive, such as writing ul, li and a styles in .nav according to HTML hierarchy relationships, but the nesting should not exceed three layers; 2. Variables and Mixin improve reusability, such as using $primary-color to define the main tone, or using @mixin to encapsulate common style blocks to reduce duplicate code; 3. Modularly organize the code structure, merge multiple small files through @import, and split styles according to functions, which facilitates team collaboration and post-maintenance.
Jul 06, 2025 am 01:39 AM
Materialized views are more suitable for scenarios where high performance is required and data latency is acceptable. 1. Materialized view physically stores query results, improving the speed of complex query, but the data is not real-time; 2. Normal view dynamically executes SQL for each query to ensure the latest data; 3. Materialized view is suitable for reporting, aggregating big data, reducing production library load, and accelerating remote database query. 4. Storage overhead and maintenance costs must be weighed when used.
Jul 06, 2025 am 01:38 AM
To make the animation loop infinitely, it needs to set its repetition mode to a continuous loop. 1. In CSS, use the animation-iteration-count property and set it to infinite; 2. In JavaScript library such as GSAP, set repeat to -1 and enable the loop option in Anime.js; 3. In mobile development, Android can set repeatCount to infinite through XML, and iOS uses the repeatForever method of SwiftUI. At the same time, attention should be paid to performance management, interactive control and cross-device testing.
Jul 06, 2025 am 01:38 AM
To run external tools in VSCode, use tasks.json to configure the task. 1. Create or edit .tasks.json file, select "Configure Task" through the command panel to generate a default template; 2. Define task attributes, such as label (task name), type (type, usually shell), command (execute command); 3. Run tasks, select "Run task" through the command panel and select the corresponding tag; 4. Integrate tools such as ESLint or Prettier, use the npx command to call locally installed tools, and set functions such as automatic running, error matching, etc.; 5. Support the passing of parameters and use of variables, such as ${file} to represent the current file; 6. Set
Jul 06, 2025 am 01:38 AM
The key to writing a good HTML5 page is clear structure and semantics, which is conducive to maintenance, SEO and barrier-free access. 1. Use appropriate semantic tags such as, ,,,,, to enhance content comprehensibility; 2. Reasonably organize page structure, maintain consistency, and flexibly use tags according to page type; 3. Avoid common semantic errors, such as multiple, abuse, untitled, and excessive nesting; 4. Combine ARIA when necessary to improve accessibility, but do not replace semantic tags to ensure smooth screen reader experience.
Jul 06, 2025 am 01:37 AM
VueTeleport is a built-in component in Vue3 that allows rendering a portion of a template to other locations in the DOM. Its core uses include: 1. Solve display problems caused by parent container layout restrictions such as modal boxes and prompt tools; 2. Move the content to the specified DOM node; 3. Keep the component logic unchanged and only change the HTML rendering position; 4. Multiple Teleports can point to the same target and stack in the rendering order; 5. When using it, make sure that the target node exists in advance and pay attention to changes in style and accessibility.
Jul 06, 2025 am 01:35 AM
HTML5 realizes network state change detection through online/offline events. The specific methods are: 1. Use window.addEventListener to listen to 'online' and 'offline' events respectively; 2. Write a callback function to handle network state changes, such as prompting the user, pausing asynchronous requests or switching local cache mode; 3. You can dynamically display the network state with the navigator.onLine attribute and DOM element. Notes include: Events only reflect whether the browser is connected to the network rather than the server accessibility. Mobile devices may frequently trigger events that require anti-shake processing, and it is recommended to improve the accuracy of judgment based on heartbeat requests.
Jul 06, 2025 am 01:35 AM
Debugging remote applications with VSCode is feasible and easy. The key is to connect local VSCode to the remote environment for remote editing and debugging. 1. Install the Remote-SSH extension and connect to the remote host through SSH; 2. Start the debug mode of the application on the remote side and open the corresponding port; 3. Configure the launch.json file to set debug parameters such as type, port and path; 4. Set breakpoints in VSCode and debug the application normally. The entire process is smooth and efficient, suitable for debugging applications running in remote environments.
Jul 06, 2025 am 01:34 AM
The key points of using v-if to render content in Vue.js include: 1. v-if decides whether to render DOM based on Boolean expressions. The element will not exist when the condition is false; 2. v-if is lazy, and the DOM will not be retained when the condition is not met. V-show should be used frequently switched; 3. Multi-condition branches can be implemented through v-else-if and v-else, and the order affects the judgment result; 4. v-else must be followed by v-if or v-else-if; 5. Use to control the display of multiple elements without adding additional DOM. Understanding these features helps to use conditional rendering correctly and efficiently.
Jul 06, 2025 am 01:34 AM
Web performance is important because users expect a quick response experience. 1.NavigationTiming API provides time stamps for each stage of page loading, such as DNS lookup, DOM loading, etc.; 2. Obtain key indicators by calculating the time difference, such as page loading time, DOM ready time, and server waiting time; 3. You can record these data with scripts and integrate them into analysis tools; 4. Other APIs such as PerformanceObserver, ResourceTiming, and LongTasks can deeply analyze performance bottlenecks; 5. It is recommended to start tracking from basic indicators and optimize user experience with resource loading information.
Jul 06, 2025 am 01:34 AM
Toimplement2FAinLaravel,usepackageslikepragmarx/google2fa-laravelorspatie/laravel-google2fa.1.Installandpublishthepackageconfiguration.2.Adda'google2fa_secret'columntotheuserstableviamigration.3.GenerateasecretkeyanddisplayaQRcodefortheusertoscanwith
Jul 06, 2025 am 01:33 AM
In Python applications, logging module should be used instead of print() to build a log system with clear structure, complete information and easy to troubleshoot problems. First, use the standard library logging instead of print() because it supports multi-level logging (DEBUG, INFO, WARNING, ERROR, CRITICAL) and can flexibly control the output format and location; second, context information, such as module name, function name, line number and key variable values, should be added to the log to improve the readability and diagnostic capabilities of the log; third, process logs according to the environment, enable the DEBUG level during development, and the production environment is limited to INFO or WARNING or above, and can be combined with files or third-party services.
Jul 06, 2025 am 01:33 AM
RMANispreferredovertraditionalbackuptoolsbecauseitoperatesatthedatabaselevel,ensuringconsistentbackupswithoutshuttingdownthedatabase.Itoffersblock-leveltracking,incrementalbackups,backupvalidation,catalogsupport,andintegratedcompressionandencryption.
Jul 06, 2025 am 01:33 AM
CSS custom properties are a key tool for implementing dynamic styles. 1. Custom attributes start with --, such as --main-color, defined in:root and called through var() to improve code maintainability; 2. Dynamic changes in theme colors are achieved through class name switching, combining JavaScript and local storage to support user preferences; 3. CSS variables can be modified in real time through JavaScript, which is suitable for color selectors, A/B testing and other scenarios; 4. Pay attention to avoiding nested use of var(), which is incompatible with IE, and the downgrade solution needs to be handled reasonably.
Jul 06, 2025 am 01:32 AM
Reflect is a built-in object in JavaScript that provides reflection operations, and Proxy is a proxy mechanism for intercepting and customizing object operations. 1.Reflect provides unified and reasonable object operation methods, such as Reflect.get and Reflect.set, which replaces old APIs with clearer and more reliable; 2. Proxy creates an object proxy to implement data binding, access control and other functions, such as Vue.js' responsive system; 3. The combination of the two can simplify code logic, maintain behavioral standards, and facilitate expansion. The Reflect method is called by default to implement basic operations; 4. When using it, you need to pay attention to performance impact, compatibility and this pointing problems to avoid abuse. Mastering them helps to develop efficient boxes
Jul 06, 2025 am 01:32 AM
The main difference between Sass and SCSS is the syntax. SCSS uses curly braces {} and semicolon similar to standard CSS; to facilitate the transition from CSS, and supports direct copying of CSS code and adding variables, mixing and other functions; while Sass adopts indented syntax, no curly braces and semicolons are required, and relies on line breaks and spaces to define code blocks. It has a simpler style but is also easy to cause problems due to format errors. The two can be converted to each other through tools. Modern frameworks mostly use SCSS by default because they are easier to learn and have rich resources; file extensions are .sass and .scss respectively, and the choice should be based on personal or team preferences.
Jul 06, 2025 am 01:31 AM
InPython,==comparesvalueswhileischecksiftworeferencespointtothesameobject.1.Use==tocomparecontentslikenumbers,strings,orlists,whichreturnsTrueifvaluesareequal.2.Useistocheckidentity,especiallyforNone,True,orFalse,asitconfirmsifvariablesrefertotheexac
Jul 06, 2025 am 01:31 AM
Optimizing CSS performance can improve loading speed and user experience. Specific methods include: 1. Reduce the complexity of selectors, replace multi-level nesting with class names, and avoid wildcards and excessive pseudo-class combinations; 2. Compress and merge CSS files, and use tools such as CSSNano to delete redundant content; 3. Prioritize loading of critical CSS and delay loading of non-critical styles; 4. Regularly check and delete unused redundant styles, and use DevTools and PurgeCSS to assist in cleaning.
Jul 06, 2025 am 01:30 AM
To update macOS applications, you can use three methods to efficiently operate: 1. Open the AppStore, click the profile icon to enter "Account Settings", click "Update All" in the "Update" section or update one by one; 2. Advanced users can run brewoutdated in Terminal to view the apps to be updated, then use brewupgrade to upgrade ordinary applications, brewupgrade--cask to upgrade cask applications; 3. For applications not installed by AppStore or Homebrew, you can find updates in the app or visit the developer's website to manually download the latest version. In addition, some third-party applications such as AdobeCreativeCloud and Microsoft
Jul 06, 2025 am 01:29 AM
In Vue3, logical sharing between components can be achieved through custom composition functions (CustomComposable). 1. Create reusable composable functions, such as useMousePosition encapsulate responsive states and side effects, for multiple components to import and use; 2. Pass the configuration through parameters, such as useFetch accepts different URLs to achieve flexible data requests; 3. Create shared state objects in combination with ref or reactive, such as user and useAuth to synchronize user information among multiple components; 4. Pay attention to cleaning up side effects, such as removing event listeners in the onUnmounted hook to avoid memory leaks; this method is compared to Mixins and higher-order
Jul 06, 2025 am 01:28 AM
Laravel middleware is a filtering layer that handles HTTP requests, which is used to uniformly process logic before the request reaches the controller. It is suitable for scenarios such as authentication, permission control, logging, cross-domain processing and current limiting. To create custom middleware, you can use the Artisan command: 1. Execute phpartisanmake:middlewareCheckToken to generate middleware; 2. Write logic in the handle method, such as verifying the request header token; 3. Register the middleware, and add it to the Kernel's $middleware array for global use, and register it to $routeMiddleware and specify it in the route. For example, the current limiting middleware can be combined with Redi
Jul 06, 2025 am 01:27 AM
Java8's Lambda expressions are implemented by simplifying anonymous internal classes, making the code more concise. 1. The basic syntax is (parameter list)->{ method body}, such as Runnabler=()->System.out.println("Hello"); 2. Commonly used for collection traversal and sorting, such as names.forEach(name->System.out.println(name)) and numbers.sort((a,b)->a.compareTo(b)); 3. It can only be used for functional interfaces, that is, interfaces with only one abstract method, such as Runnable
Jul 06, 2025 am 01:27 AM
In Linux systems, the most common way to view directory size is to use the du command. 1. Use du-sh/path/to/directory to view the total size of the specified directory, where -s represents summary and -h represents display in a human-readable manner; 2. Use du-h/path/to/directory to list the size of each subdirectory and file in the directory; 3. Use du-h-d1/path/to/directory to limit the display level, such as only displaying first-level subdirectories; 4. Use du-h/path/to/directory to sort by size, and combine head-n20 to display the first 20 results for easy finding.
Jul 06, 2025 am 01:26 AM
In web development, communication between the main thread and HTML5WebWorker is implemented through the postMessage method; 1. Create a Worker instance and send messages using postMessage; 2. Receive messages through onmessage in worker.js and use postMessage to pass back; 3. Support the transmission of strings, numbers, arrays, objects and other data types, but attention should be paid to structured cloning restrictions and performance issues; 4. Transferring ArrayBuffer can improve transmission efficiency; 5. Handling complex tasks and callback logic through task ID and custom event design protocol.
Jul 06, 2025 am 01:25 AM
