超级简单的下载与进度条 [英] Super simple download with progress bar

问题描述

在AutoHotkey中设置异步下载是一件很痛苦的事情，但是如果您想在下载过程中运行一些代码，例如更新进度条，这是必要的。

Setting up an asynchronous download in AutoHotkey is a pain, but this is is necessary if you want to run some code during the download, like for example updating progress bar.

所以问题是：
有没有一个简单而简单的方式下载一个进度条的文件，而不包括巨大的1000多行库？

So the question is: Is there a short and simple way of downloading a file with a progress bar, without including huge 1000+ lines libraries?

推荐答案

我早就想出了这个代码，你仍然可以在AHK论坛上找到它，但是为什么不和Stackoverflow社区分享：

I came up with that code quite some time ago and you can still find it on the AHK forums, however, why not share it with the Stackoverflow community:

DownloadFile(UrlToFile, SaveFileAs, Overwrite := True, UseProgressBar := True) {
    ;Check if the file already exists and if we must not overwrite it
      If (!Overwrite && FileExist(SaveFileAs))
          Return
    ;Check if the user wants a progressbar
      If (UseProgressBar) {
          ;Initialize the WinHttpRequest Object
            WebRequest := ComObjCreate("WinHttp.WinHttpRequest.5.1")
          ;Download the headers
            WebRequest.Open("HEAD", UrlToFile)
            WebRequest.Send()
          ;Store the header which holds the file size in a variable:
            FinalSize := WebRequest.GetResponseHeader("Content-Length")
          ;Create the progressbar and the timer
            Progress, H80, , Downloading..., %UrlToFile%
            SetTimer, __UpdateProgressBar, 100
      }
    ;Download the file
      UrlDownloadToFile, %UrlToFile%, %SaveFileAs%
    ;Remove the timer and the progressbar because the download has finished
      If (UseProgressBar) {
          Progress, Off
          SetTimer, __UpdateProgressBar, Off
      }
    Return

    ;The label that updates the progressbar
      __UpdateProgressBar:
          ;Get the current filesize and tick
            CurrentSize := FileOpen(SaveFileAs, "r").Length ;FileGetSize wouldn't return reliable results
            CurrentSizeTick := A_TickCount
          ;Calculate the downloadspeed
            Speed := Round((CurrentSize/1024-LastSize/1024)/((CurrentSizeTick-LastSizeTick)/1000)) . " Kb/s"
          ;Save the current filesize and tick for the next time
            LastSizeTick := CurrentSizeTick
            LastSize := FileOpen(SaveFileAs, "r").Length
          ;Calculate percent done
            PercentDone := Round(CurrentSize/FinalSize*100)
          ;Update the ProgressBar
            Progress, %PercentDone%, %PercentDone%`% Done, Downloading...  (%Speed%), Downloading %SaveFileAs% (%PercentDone%`%)
      Return
}

以下是一些示例：

示例1 - 使用进度条下载firefox设置，如果磁盘上已存在，则覆盖它：

DownloadFile("http://download-installer.cdn.mozilla.net/pub/firefox/releases/26.0/win32/en-US/Firefox%20Setup%2026.0.exe", "firefox_setup.exe")

示例2 - 使用进度条下载Autohotkey，如果已存在，请勿覆盖它：

Url = http://ahkscript.org/download/ahk-install.exe
DownloadAs = AutoHotkey_L Installer.exe
Overwrite := False
UseProgressBar := True
DownloadFile(Url, DownloadAs, Overwrite, UseProgressBar)

示例3 - 下载CCleaner设置并打开另存为对话框，要求用户保存文件，如果已存在则覆盖该文件：

FileSelectFile, SaveAs, S, ccsetup410.exe
DownloadFile("http://download.piriform.com/ccsetup410.exe", SaveAs, True, True)

这篇关于超级简单的下载与进度条的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！