ios - 快速写入文件

Question

这是我在 appDelegate didFinishLaunchingWithOptions() 中的代码

  var paths : NSArray =  NSSearchPathForDirectoriesInDomains(.DocumentDirectory, .UserDomainMask, true)
    var documentsDirectory = paths.objectAtIndex(0)
    var fileName: String = String(format: "Logger.txt")
    var logFilePath : NSString = documentsDirectory.stringByAppendingPathComponent(fileName)
    freopen(logFilePath, "a+", stderr)

我得到的错误是无法将 NSString 转换为 UnSafepointer。谁能帮我实现这个？

Answer 1

只需从 logFilePath 中删除 NSString:

var paths : NSArray =  NSSearchPathForDirectoriesInDomains(.DocumentDirectory, .UserDomainMask, true)
var documentsDirectory = paths.objectAtIndex(0)
var fileName: String = String(format: "Logger.txt")
var logFilePath = documentsDirectory.stringByAppendingPathComponent(fileName)
freopen(logFilePath, "a+", stderr)

更安全的方法是这样的:

let file = "Logger.txt"
let text = "A safer way to do this"

if let directory : NSString = NSSearchPathForDirectoriesInDomains(NSSearchPathDirectory.DocumentDirectory, NSSearchPathDomainMask.AllDomainsMask, true).first {
    let path = directory.stringByAppendingPathComponent(file);

    print(path)

    do {
        try text.writeToFile(path, atomically: false, encoding: NSUTF8StringEncoding)
    }
    catch {
    }
}