c# – ASP.NET计划删除临时文件

问题：我有一个ASP.NET应用程序,可以创建临时PDF文件(供用户下载).
现在,许多用户在很多天内都可以创建许多PDF,这需要占用大量磁盘空间.

安排删除超过1天/ 8小时的文件的最佳方法是什么？
最好是在asp.net应用程序本身…

解决方法:

对于您需要创建的每个临时文件,请在会话中记下文件名：

// create temporary file:
string fileName = System.IO.Path.GetTempFileName();
Session[string.Concat("temporaryFile", Guid.NewGuid().ToString("d"))] = fileName;
// TODO: write to file

接下来,将以下清理代码添加到global.asax：

<%@ Application Language="C#" %>
<script RunAt="server">
    void Session_End(object sender, EventArgs e) {
        // Code that runs when a session ends. 
        // Note: The Session_End event is raised only when the sessionstate mode
        // is set to InProc in the Web.config file. If session mode is set to StateServer 
        // or SQLServer, the event is not raised.

        // remove files that has been uploaded, but not actively 'saved' or 'canceled' by the user
        foreach (string key in Session.Keys) {
            if (key.StartsWith("temporaryFile", StringComparison.OrdinalIgnoreCase)) {
                try {
                    string fileName = (string)Session[key];
                    Session[key] = string.Empty;
                    if ((fileName.Length > 0) && (System.IO.File.Exists(fileName))) {
                        System.IO.File.Delete(fileName);
                    }
                } catch (Exception) { }
            }
        }

    }       
</script>

更新：我现在正在使用一种新的(改进的)方法而不是上述的方法.新的涉及HttpRuntime.Cache并检查文件是否超过8小时.如果有兴趣的话,我会在这里发布.这是我的新global.asax.cs：

using System;
using System.Web;
using System.Text;
using System.IO;
using System.Xml;
using System.Web.Caching;

public partial class global : System.Web.HttpApplication {
    protected void Application_Start() {
        RemoveTemporaryFiles();
        RemoveTemporaryFilesSchedule();
    }

    public void RemoveTemporaryFiles() {
        string pathTemp = "d:\\uploads\\";
        if ((pathTemp.Length > 0) && (Directory.Exists(pathTemp))) {
            foreach (string file in Directory.GetFiles(pathTemp)) {
                try {
                    FileInfo fi = new FileInfo(file);
                    if (fi.CreationTime < DateTime.Now.AddHours(-8)) {
                        File.Delete(file);
                    }
                } catch (Exception) { }
            }
        }
    }

    public void RemoveTemporaryFilesSchedule() {
        HttpRuntime.Cache.Insert("RemoveTemporaryFiles", string.Empty, null, DateTime.Now.AddHours(1), Cache.NoSlidingExpiration, CacheItemPriority.NotRemovable, delegate(string id, object o, CacheItemRemovedReason cirr) {
            if (id.Equals("RemoveTemporaryFiles", StringComparison.OrdinalIgnoreCase)) {
                RemoveTemporaryFiles();
                RemoveTemporaryFilesSchedule();
            }
        });
    }
}

标签：c,asp-net,vb-net,scheduled-tasks,temporary-files
来源： https://codeday.me/bug/20190526/1158926.html