August 2022

At work, we often need to view the real-time network card traffic of the server. Usually, we will view the real-time network card traffic of the Linux server in these ways. Table of contents 1. sar 2. /proc/net/dev 3. ifstat 4. iftop 5. nload 6. iptraf-ng 7. nethogs 8. Expansion 1. sar The sar command

I. Introduction When the website is doing an activity, a prompt will appear with a countdown to the deadline. The effect is as shown in the figure: 2. Analysis ①Reminder time is constantly changing every second, you need to use timer (setInterval) //1000表示每隔一秒变化一次，单位为毫秒setInterval(countDown, 1000); ②The three boxes are assigned values ​​through innerHTML, and the hours,

1. Google Chrome F12 2. Right-click on the header 3. If gzip is enabled, gzip will be displayed, if not, it will be empty … The post How to see if a page has gzip compression turned on first appeared on Lenix Blog . This article is reprinted from https://blog.p2hp.com/archives/9288 This site is for inclusion

What is a preflight request? preflight, a cors preflight request, belongs to the options request. This request is made automatically by the browser when it thinks that an upcoming request might have unpredictable effects on the server. Using the preflight request, the browser can know whether the current server allows the execution of the upcoming

1. Open any browser. This article takes the chrome browser as an example. After opening, press F12 to enter the developer mode and click the [Console] tab. 2. In the [Console] tab, write js code, first assign the current date and time to a js variable curTime, the code is as follows: var curTime =

js uses ‘+’ before a data type. The purpose of this operation is to convert the data type to Number type. If the conversion fails, it will return NaN; E.g: + ‘2’ + 1 // 3 + [ 1 ] // NaN +new Date() will call the valueOf method on Date.prototype, according to new Date().getTime()