swift - DispatchQueue.main.asyncAfter(截止日期: ) not working in command line app

Question

这个问题已经有答案了:

How to prevent a Command Line Tool from exiting before asynchronous operation completes (8 个回答)

已关闭 4 年前。

我正在尝试制作一个程序，每秒从 txt 文件粘贴一个句子。它可以在没有 DispatchQueue.main.asyncAfter(deadline: ) 的情况下工作。有了它，它什么也不打印，并立即以退出代码 0 结束。程序如下:

import Cocoa

let file = "slowreadText.txt"
let waitTime: TimeInterval = 1

if let dir = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask).first {

    let fileURL = dir.appendingPathComponent(file)

    do {
        let text = try String(contentsOf: fileURL, encoding: .utf8)
        let sentences = text.components(separatedBy: ".")

        for i in 0..<sentences.count {
            let sentence = sentences[i]
            DispatchQueue.main.asyncAfter(deadline: .now() + (waitTime * Double(i))) {
                print(sentence)
            }
        }

    }catch {
        print(error)
    }
}

Answer 1

您需要在脚本末尾调用 RunLoop.main.run() 以防止其终止。