Question

给定一个路径[[self documentsDirectory] stringByAppendingPathComponent:@"myFiles/aFile.txt"]的文件，如何删除我的应用文档目录中的文件？

Answer 1

NSFileManager是一个非常方便的工具：

[[NSFileManager defaultManager] removeItemAtPath: pathToFile error: &error];

Answer 2

使用Swift 3，FileManager有一个名为removeItem(at:)的方法。 removeItem(at:)有以下声明：

func removeItem(at URL: URL) throws

删除指定网址的文件或目录。

下面的代码片段显示了如何使用removeItem(at:)删除文件：

do {
    try FileManager.default.removeItem(at: fileUrl)
} catch {
    print("Could not delete file: \(error)")
}

作为一个完整的示例，以下UIViewController子类实现显示了如何将文件从应用程序包复制到文档目录中的特定URL，删除文档目录中特定URL的文件并检查是否存在文件存在于文档目录中的特定URL：

import UIKit

class ViewController: UIViewController {

    @IBAction func copyFile(_ sender: UIButton) {
        // Get app bundle file url
        guard let bundleFileUrl = Bundle.main.url(forResource: "Movie", withExtension: "mov") else { return }

        // Create a destination url in document directory for file
        guard let documentsDirectory = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask).first else { return }
        let documentDirectoryFileUrl = documentsDirectory.appendingPathComponent("Movie.mov")

        // Copy bundle file to document directory
        if !FileManager.default.fileExists(atPath: documentDirectoryFileUrl.path) {
            do {
                try FileManager.default.copyItem(at: bundleFileUrl, to: documentDirectoryFileUrl)
            } catch {
                print("Could not copy file: \(error)")
            }
        }
    }

    @IBAction func deleteFile(_ sender: UIButton) {
        // Get destination url in document directory for file
        guard let documentsDirectory = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask).first else { return }
        let documentDirectoryFileUrl = documentsDirectory.appendingPathComponent("Movie.mov")

        // Delete file in document directory
        if FileManager.default.fileExists(atPath: documentDirectoryFileUrl.path) {
            do {
                try FileManager.default.removeItem(at: documentDirectoryFileUrl)
            } catch {
                print("Could not delete file: \(error)")
            }
        }
    }

    @IBAction func checkIfFileExist(_ sender: UIButton) {
        // Get destination url in document directory for file
        guard let documentsDirectory = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask).first else { return }
        let outputUrl = documentsDirectory.appendingPathComponent("Movie.mov")

        // Print if file exists in document directory or not
        FileManager.default.fileExists(atPath: outputUrl.path) ? print("File exists") : print("File does not exist")
    }

}

Answer 3

对于Swift 3.x和Xcode 8.x

itemName - 将文件存储在文档目录中的名称

文件扩展名 - 文件扩展名

var featureLayer = new FeatureLayer({
                    url: "https://services.arcgis.com/P3ePLMYs2RVChkJx/arcgis/rest/services/USA_Census_Tract_Areas_analysis_trim/FeatureServer/0",
                    outFields: ["*"],
                    renderer: renderer,
                    definitionExpression: "FIPS IN (" + fips + ")"
                });

如何删除应用程序文档目录中的文件？

3 个答案: