In ASP.NET, we can achieve this by FileStream.FileStream(string path, FileMode mode, FileAccess access); as below:

var fileStream = new FileStream(Server.MapPath("~/key.crt"), FileMode.Open, FileAccess.Read);
string text;
using (var streamReader = new StreamReader(fileStream, Encoding.UTF8))
{
    text = streamReader.ReadToEnd();
}
Response response = new Response(text, samlTmp);

Can we achieve same in .NET Core? I need to pass file path and specify file mode along with the file read/write permission.

I have tried File.Open(). But I get this error even after adding the namespace using System.IO;

The name 'Server' does not exist in the current context

CodePudding user response：

Use System.IO.File.Open(path, FileMode, FileAccess) instead

https://docs.microsoft.com/fr-fr/dotnet/api/system.io.file.open?view=net-6.0#system-io-file-open(system-string-system-io-filemode-system-io-fileaccess)

var fileStream = System.IO.File.Open(path, FileMode.Open, FileAccess.Read);

CodePudding user response：

So two things

1. File is an method on your Controller. You need to use the full name System.IO.File
2. In .NET Core you should inject IWebHostEnvironment and then call environment.ContentRootFileProvider.GetFileInfo("/key.crt").PhysicalPath to resolve the relative path to your key file.

All in all, your example could look like this instead

public IActionResult YourMethod([FromService]IWebHostEnvironment environment)
{
    var fileStream = System.IO.File.Open(environment.ContentRootFileProvider.GetFileInfo("/key.crt").PhysicalPath, FileMode.Open, FileAccess.Read);
    string text;
    using (var streamReader = new StreamReader(fileStream, Encoding.UTF8))
    {
        text = streamReader.ReadToEnd();
    }
    Response response = new Response(text, samlTmp);
......

You should also be able to reduce

var fileStream = System.IO.File.Open(environment.ContentRootFileProvider.GetFileInfo("/key.crt").PhysicalPath, FileMode.Open, FileAccess.Read);

to

var fileStream = environment.ContentRootFileProvider.GetFileInfo("/key.crt").CreateReadStream();