无法使用类型为“（字符串，withIntermediateDirectories：B）的参数列表调用“createDirectoryAtPath”答案

【问题标题】：Cannot invoke 'createDirectoryAtPath' with an argument list of type '(String, withIntermediateDirectories: B无法使用类型为“（字符串，withIntermediateDirectories：B）的参数列表调用“createDirectoryAtPath”
【发布时间】：2015-10-07 07:42:13
【问题描述】：

我正在为 sqlite 数据库使用 SwiftData 框架。当我将 Xcode 表单 6.4 更新到 7.0.1 时，swift data.swift 文件显示此错误'。我提供了下面的代码。

public static func saveUIImage(image: UIImage) -> String? {

        let docsPath = NSSearchPathForDirectoriesInDomains(NSSearchPathDirectory.DocumentDirectory, NSSearchPathDomainMask.UserDomainMask, true)[0] as String
        let imageDirPath = docsPath.stringByAppendingPathComponent("SwiftDataImages")
        if !NSFileManager.defaultManager().fileExistsAtPath(imageDirPath) {
            if !NSFileManager.defaultManager().createDirectoryAtPath(imageDirPath, withIntermediateDirectories: false, attributes: nil, error: nil) {
                print("Error creating SwiftData image folder")
                return nil
            }
        }
        let imageID = NSUUID().UUIDString
        let imagePath = imageDirPath.stringByAppendingPathComponent(imageID)
        let imageAsData = UIImagePNGRepresentation(image)
        if !imageAsData!.writeToFile(imagePath, atomically: true) {
            print("Error saving image")
            return nil
        }
        return imageID

    }

【问题讨论】：

标签： ios swift swift2 xcode7

【解决方案1】：

createDirectoryAtPath 语法更改为：

- (BOOL)createDirectoryAtPath:(NSString *)path withIntermediateDirectories:(BOOL)createIntermediates attributes:(nullable NSDictionary<NSString *, id> *)attributes error:(NSError **)error NS_AVAILABLE(10_5, 2_0);

所以你可以像这样更新你的代码：

NSFileManager.defaultManager().createDirectoryAtPath(imageDirPath, withIntermediateDirectories: false, attributes: [:])

然后你用 swift 2.0 完成代码：

func saveUIImage(image: UIImage) -> String? {

    let docsPath = NSSearchPathForDirectoriesInDomains(NSSearchPathDirectory.DocumentDirectory, NSSearchPathDomainMask.UserDomainMask, true)[0] as String
    let imageDirPath = (docsPath as NSString).stringByAppendingPathComponent("SwiftDataImages")
    if !NSFileManager.defaultManager().fileExistsAtPath(imageDirPath) {

        do{
            try NSFileManager.defaultManager().createDirectoryAtPath(imageDirPath, withIntermediateDirectories: false, attributes: [:])
        } catch {
            print("Error creating SwiftData image folder")
            return nil
        }
    }
    let imageID = NSUUID().UUIDString
    let imagePath = (imageDirPath as NSString).stringByAppendingPathComponent(imageID)
    let imageAsData = UIImagePNGRepresentation(image)
    if !imageAsData!.writeToFile(imagePath, atomically: true) {
        print("Error saving image")
        return nil
    }
    return imageID
}

或者您可以为stringByAppendingPathComponent 使用扩展名，因为它在2.0 中不适用于String。

extension String {

    func stringByAppendingPathComponent(path: String) -> String {

        let nsSt = self as NSString

        return nsSt.stringByAppendingPathComponent(path)
    }
}

你可以这样使用它：

let imageDirPath = docsPath.stringByAppendingPathComponent("SwiftDataImages")
let imagePath = imageDirPath.stringByAppendingPathComponent(imageID)

【讨论】：