I want Check exist file

Hi All.

I made Console Application Check exist file from forder of server.

label.Text = System.IO.File.Exists(@"\\nar-serverPC500s3\test\memo\choco\ice\abc.xlsx").ToString();

And I got return True.

But If i write same source in SharePoint Webpart, I get false.

So...I found this http://msdn.microsoft.com/en-us/library/microsoft.sharepoint.client.file.exists.aspx

But I don`t know means use this class

Microsoft.SharePoint.Client.File. <- not exist property "exists"

please i need your help. Thnks