使用c＃检查文件是否存在

I stored a file path in database table like this ../Document/5292013/cal.png. Now I want to check whether or not the file exists in the server folder. I am using the below code to check this, but it's not working for me.

我在这样的数据库表中存储了一个文件路径../Document/5292013/cal.png。现在我想检查文件是否存在于服务器文件夹中。我使用下面的代码检查这个,但它不适合我。

 if (File.Exists(Server.MapPath(root.GetElementsByTagName("FLD_DOC_ID")[0].InnerText)))
 {
     proof.HRef = Server.MapPath(root.GetElementsByTagName("FLD_DOC_ID")[0].InnerText);
 }

Now I check using watch File.Exists(Server.MapPath("Document")) //Returns false, but server having the same folder.

现在我检查使用watch File.Exists(Server.MapPath(“Document”))//返回false,但服务器具有相同的文件夹。

Please help me to solve this.

请帮我解决这个问题。

3 个解决方案

#1

You need to transform the file name to a virtual form before using MapPath. You must know the specifics of how it needs to be done. For example:

在使用MapPath之前,需要将文件名转换为虚拟表单。您必须知道需要如何完成的具体细节。例如:

string fileName = root.GetElementsByTagName("FLD_DOC_ID")[0].InnerText;
fileName = fileName.Replace("..", "~");
if (File.Exists(Server.MapPath(fileName))
{
    // you probably do not want MapPath here:
    //proof.HRef = Server.MapPath(root.GetElementsByTagName("FLD_DOC_ID")[0].InnerText);
    proof.HRef = System.Web.VirtualPathUtility.ToAbsolute(fileName);
}

#2

Try to print out Server.MapPath(root.GetElementsByTagName("FLD_DOC_ID")[0].InnerText) it might be pointing a wrong path or something

尝试打印出Server.MapPath(root.GetElementsByTagName(“FLD_DOC_ID”)[0] .InnerText)它可能指向错误的路径或某事

Any way, checking a file if it exists or not is very trivial:

无论如何,检查文件是否存在都非常简单:

if(File.Exists(the file path))
{

}

#3

First you have to get filepath (filename) from database using select query then use that path with file.exists.

首先,您必须使用select query从数据库获取filepath(filename),然后将该路径与file.exists一起使用。

Example:

First get filename or filepath from database then,

首先从数据库获取文件名或文件路径,然后,

if you get only filename then use below code:

如果你只获得文件名,那么使用下面的代码:

if(File.Exits(Server.MapPath("Document/5292013/"+filename)))
{
}

or if you get only filepath then use below code:

或者如果你只获得filepath,那么使用下面的代码:

if(File.Exits(Server.MapPath("filename")))
{
}

Thanks

#1