once the default value of the parameter is set, the parameter forms a separate context when the function is declared to initialize. When initialization is complete, the scope disappears. This syntax behavior is not an extension of the function when th...
I have just learned python and encountered some problems about the scope of variables, as follows: the following is not very clear var a = 3 const f = () => { a += 4 console.log(a) } a() 7 f() 7 in js , you can not only access gl...
how does express determine the device type to return to the home page under different paths when the user accesses the primary domain name? if you visit mobile phone and PC, visit www. respectively. The domain name .com returns a different index home pa...
at present, there is a need to count the data of some dailies and show them with echarts. Because it may involve calculating the sum of months or years according to the day, I hope to find a way to do the calculation instead of mysql. The first thing th...
<template> <div class="car"> <h3 style="text-align: center;">< h3> <ul> <li v-for="(item,index) in carts" :key="index"> <div class=&qu...
I use the iview component library (2.11.0) and follow the instructions on the official website https: www.iviewui.com docs . to use the date component, but in the local project, the font icon is not loaded, as shown in figure this is how I introduc...
A question is that a div snooping touchend controls video playback. In ios, if you swipe over the div and eventually leave the finger, although the code in the touchend is executed, the video is not played. What is the reason? Android normal ...