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I have a page that allows users to download dynamically generated files. Generation takes a long time, so I want to display a "wait" indication. The problem is, I don't know how to detect when a browser receives a file, so I can hide the indicator. I'm making a request in a hidden form, which is published to the server and results ...

It's hard for me to figure out how to move array elements. For example, the following is given: var arr = [ 'a', 'b', 'c', 'd', 'e']; Why can I write 'b' before the mobile function 'd'? Or 'c' after 'a'? After the move, the indexes of the remaining elements should be updated. This means that in the first example, after moving, arr [ ...

Functional requirements, click the administrative region, and the pop-up box will show the administrative region of the city (Note: the following data is only for demonstration, and does not represent its authenticity) 1, Screenshot description function requirements: 2. Implementation steps: 1. Get page parameters Get the ...

Yesterday, I wrote a small crawler. When using axios.all to request multiple pages at the same time, it's easy for the reasons of the domestic network to time out and reject. It's not advisable for Buddhist resolve. Then I thought that I could realize a function of "resending failed requests". Promise.all(requestPromises).then(...).ca ...

mui single webview mode, the page is as follows. There are two poppickers on it, and then the page can't slide up and down. <div class="mui-content us-reimburse"> <div class="block"> <div class="us-list-title"> Application information &lt ...

Catalog Overview Image size adjustment algorithm How to use controls on Web pages? How to get the uploaded image from the control? source code Reference Overview We have long-term problems with image resizing and cropping. Our problem is that if we resize on the server side, the image qualit ...

I'm trying to create a fast 2D point inside the polygon algorithm for hit testing (for example, Polygon.contains(p:Point)). Suggestions for effective technology will be appreciated. #1 building The C version of nirg's answer is here: I only share the code. This can save some time. public static bool IsPointInPolygon(IList<Point> ...

16. The pit in useeffect and the status before using useRef to record 1. Scene description Usage when using useEffect hooks, we will add a dependency to it to complete some side effects when one or some dependencies change. The normal usage is as follows: import React, { useEffect, useState } from " ...

In JavaScript code, using regular expressions for pattern matching often uses some methods of String object and RegExp object, such as replace, match, search and so on. The following is a summary of some methods. There are four ways to support regular expressions in String objects: search, replace, matc ...

Native JavaScript+Css Simulated Select Dropdown Preface Implementation Details Technology involved Effect Display Code Display Html structure Css structure JavaScript structure summary Preface Hello, FEer s!In our front-end development career, there are many details, some need to be compatib ...