Rebol 程式設計/request-download

用法

REQUEST-DOWNLOAD url /to local-file 

描述

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REQUEST-DOWNLOAD 是一個函式值。

引數

• url -- (型別：url)

細化

• /to -- 指定本地檔案目標。
  • local-file -- (型別：檔案無)

原始碼

request-download: func [
    {Request a file download from the net. Show progress. Return none on error.} 
    url [url!] 
    /to "Specify local file target." local-file [file! none!] 
    /local prog lo stop data stat event-port event
][
    view/new center-face lo: layout [
        backeffect [gradient 1x1 water gray] 
        space 10x8 
        vh2 300 gold "Downloading File:" 
        vtext bold center 300 to-string url 
        prog: progress 300 
        across 
        btn 90 "Cancel" [stop: true] 
        stat: text 160x24 middle
    ] 
    stop: false 
    data: read-thru/to/progress/update url local-file func [total bytes] [
        prog/data: bytes / (max 1 total) 
        stat/text: reform [bytes "bytes"] 
        show [prog stat] 
        not stop
    ] 
    unview/only lo 
    if not stop [data]
]