在Swift中获取文件大小

Question

我尝试了几种方法来获取文件大小，但始终为零。

let path = NSBundle.mainBundle().pathForResource("movie", ofType: "mov")
let attr = NSFileManager.defaultManager().attributesOfFileSystemForPath(path!, error: nil)
if let attr = attr {
    let size: AnyObject? = attr[NSFileSize]
    println("File size = \(size)")
}

我在日志中： File size = nil

Answer 1

使用attributesOfItemAtPath而不是attributesOfFileSystemForPath
+调用attr上的.fileSize（）。

var filePath: NSString = "your path here"
var fileSize : UInt64
var attr:NSDictionary? = NSFileManager.defaultManager().attributesOfItemAtPath(filePath, error: nil)
if let _attr = attr {
    fileSize = _attr.fileSize();
}

在Swift 2.0中，我们使用do try catch模式，如下所示：

let filePath = "your path here"
var fileSize : UInt64 = 0

do {
    let attr : NSDictionary? = try NSFileManager.defaultManager().attributesOfItemAtPath(filePath)

    if let _attr = attr {
        fileSize = _attr.fileSize();
    }
} catch {
    print("Error: \(error)")
}

在Swift 3.x / 4.0中：

let filePath = "your path here"
var fileSize : UInt64

do {
    //return [FileAttributeKey : Any]
    let attr = try FileManager.default.attributesOfItem(atPath: filePath)
    fileSize = attr[FileAttributeKey.size] as! UInt64

    //if you convert to NSDictionary, you can get file size old way as well.
    let dict = attr as NSDictionary
    fileSize = dict.fileSize()
} catch {
    print("Error: \(error)")
}