如何将 UnsafeMutablePointer<UnsafeMutablePointer<Int8>?> 转换为 UnsafeMutablePointer<Unsafe

Posted 2023-02-24

【中文标题】如何将 UnsafeMutablePointer<UnsafeMutablePointer<Int8>?> 转换为 UnsafeMutablePointer<UnsafeMutablePointer<Int8>>！

【英文标题】：how to convert UnsafeMutablePointer<UnsafeMutablePointer<Int8>?> to UnsafeMutablePointer<UnsafeMutablePointer<Int8>>!

【发布时间】：2017-09-30 06:14:02

【问题描述】：

我正在使用 swift 4.0 重写我的 ios 应用程序的 main.swift。 这是我的 main.swift：

UIApplicationMain(CommandLine.argc,
              CommandLine.unsafeArgv
              NSStringFromClass(MyAPP.self),
              NSStringFromClass(AppDelegate.self))

这里有一个编译错误：

Cannot convert value of type 'UnsafeMutablePointer<UnsafeMutablePointer<Int8>?>' to expected argument type 'UnsafeMutablePointer<UnsafeMutablePointer<Int8>>!'

有人知道如何在这里将UnsafeMutablePointer<UnsafeMutablePointer<Int8>?> 转换为UnsafeMutablePointer<UnsafeMutablePointer<Int8>>! 吗？

【问题讨论】：

Xcode 8 beta 6: main.swift won't compile的可能重复

【参考方案1】：

UIApplicationMain(
    CommandLine.argc,
    UnsafeMutablePointer(CommandLine.unsafeArgv),
    NSStringFromClass(MyAPP.self),
    NSStringFromClass(AppDelegate.self)
)

【讨论】：

考虑添加一些说明您的代码解决问题的原因。

UnsafeMutableRawPointer(CommandLine.unsafeArgv) 已弃用。

【参考方案2】：

请检查：

UIApplicationMain(  
    CommandLine.argc,  
    UnsafeMutableRawPointer(CommandLine.unsafeArgv)  
        .bindMemory(  
            to: UnsafeMutablePointer<Int8>.self,  
            capacity: Int(CommandLine.argc)
        ),  
    NSStringFromClass(MyAPP.self),  
    NSStringFromClass(AppDelegate.self)  
)  

【讨论】：

这是一个弃用的答案