Programmer Group

brief introduction Drag-and-drop is a common feature, which is to drag an object to another location after grabbing it. In HTML5, drag and drop is part of the standard, and any element can be dragged and dropped. First click on a small example: execute JavaScript when the user starts dragging < p > elements <p draggable="true" ondragst ...

From: http://geek.csdn.net/news/detail/199421 The benefit of the JavaScript ServiceWorker API is that it allows web developers to easily control the cache.Although technologies such as ETags are also used to control the cache, using JavaScript allows programs to control the cache more powerful and free.Of course, there are powerful benefit ...

Linux systems can view information such as CPU, memory, run time, swap partitions, thread of execution of the system through the top command.The top command is an effective way to find out what's wrong with your system.Not enough memory, not enough CPU processing power, too high IO reading and writing.... [root@foundation6 docker]# top top - ...

Preface _At present, the optimization of front-end development has a complete set of routines, including js, css optimization, HTML optimization, first-screen data request optimization, etc. This paper mainly discusses the front-end development. Optimizing ideas for sending ajax requests. Number of concurrent requests from browsers _The ...

1. Content Generation Role: Adding new content to existing tags using css Method: Through pseudo-element selector (before, after) 1. Attribute:content 2. Value: 1. String: plain text, caused by the use of "" 2. url(): Generate an image to a specified content area 3. Counter Using content generation to generate icons ...

title: 2017-9-26 html model and centralization method date: 2017-09-26 18:07:38 tags: [HTML5,CSS3] grammar_cjkRuby: true Welcome to my personal blog Personal Blog of Never Island HTML model Box model The box model can be imagined as a packaged moon cake, div, content, padding between the moon cake and the box, margin between the ...

Browser calls camera getUserMedia The news of QQ browser launching in 2018 will boot the camera is full of buzz.Some time ago, the company asked to study the browser to enable the camera function, hoping to achieve the browser web page scanning two-dimensional code function. Now write it down and record it. Browser-enabled cam ...

File upload 1. Upload Form Restrictions method="post" enctype="multipart/form-data" File form entries need to be added to the form: <input type="file" name="xxx"/> <h3>${msg }</h3> <form action="xxx" method="post" enctype="multipart/form-data"> //User name; <input type="text" nam ...

A previous visual computing project called receiving the front-end, so there is a strange demand that the front-end opens the camera, and at the same time needs to send the camera data back to the back-end for image processing (such as beauty ah head with an ornament and so on), which involves data coding coupling between the front-end and the ...

Introduction to websocket Scenario: Background management of a mall system, to achieve if there is customer order in the foreground, the background will receive messages, so as to ship processing as soon as possible. To achieve these functions, there are several alternatives. Scenario 1. Use ajax short polling, such as reque ...