FileInfo.Length Proprietà
Definizione
Importante
Alcune informazioni sono relative alla release non definitiva del prodotto, che potrebbe subire modifiche significative prima della release definitiva. Microsoft non riconosce alcuna garanzia, espressa o implicita, in merito alle informazioni qui fornite.
Ottiene le dimensioni in byte del file corrente.
public:
property long Length { long get(); };
public long Length { get; }
member this.Length : int64
Public ReadOnly Property Length As Long
Valore della proprietà
Dimensione del file corrente espressa in byte.
Eccezioni
Refresh() non può aggiornare lo stato del file o della directory.
Il file specificato non esiste.
-oppure-
Viene chiamata la proprietà Length
per una directory.
Esempio
Nell'esempio seguente vengono visualizzate le dimensioni dei file specificati.
// The following example displays the names and sizes
// of the files in the specified directory.
using namespace System;
using namespace System::IO;
int main()
{
// Make a reference to a directory.
DirectoryInfo^ di = gcnew DirectoryInfo( "c:\\" );
// Get a reference to each file in that directory.
array<FileInfo^>^fiArr = di->GetFiles();
// Display the names and sizes of the files.
Console::WriteLine( "The directory {0} contains the following files:", di->Name );
System::Collections::IEnumerator^ myEnum = fiArr->GetEnumerator();
while ( myEnum->MoveNext() )
{
FileInfo^ f = safe_cast<FileInfo^>(myEnum->Current);
Console::WriteLine( "The size of {0} is {1} bytes.", f->Name, f->Length );
}
}
//This code produces output similar to the following;
//results may vary based on the computer/file structure/etc.:
//
//The directory c:\ contains the following files:
//The size of MyComputer.log is 274 bytes.
//The size of AUTOEXEC.BAT is 0 bytes.
//The size of boot.ini is 211 bytes.
//The size of CONFIG.SYS is 0 bytes.
//The size of hiberfil.sys is 1072775168 bytes.
//The size of IO.SYS is 0 bytes.
//The size of MASK.txt is 2700 bytes.
//The size of mfc80.dll is 1093632 bytes.
//The size of mfc80u.dll is 1079808 bytes.
//The size of MSDOS.SYS is 0 bytes.
//The size of NTDETECT.COM is 47564 bytes.
//The size of ntldr is 250032 bytes.
//The size of pagefile.sys is 1610612736 bytes.
//The size of UpdatePatch.log is 22778 bytes.
//The size of UpdatePatch.txt is 30 bytes.
//The size of wt3d.ini is 234 bytes.
// The following example displays the names and sizes
// of the files in the specified directory.
using System;
using System.IO;
public class FileLength
{
public static void Main()
{
// Make a reference to a directory.
DirectoryInfo di = new DirectoryInfo("c:\\");
// Get a reference to each file in that directory.
FileInfo[] fiArr = di.GetFiles();
// Display the names and sizes of the files.
Console.WriteLine("The directory {0} contains the following files:", di.Name);
foreach (FileInfo f in fiArr)
Console.WriteLine("The size of {0} is {1} bytes.", f.Name, f.Length);
}
}
//This code produces output similar to the following;
//results may vary based on the computer/file structure/etc.:
//
//The directory c:\ contains the following files:
//The size of MyComputer.log is 274 bytes.
//The size of AUTOEXEC.BAT is 0 bytes.
//The size of boot.ini is 211 bytes.
//The size of CONFIG.SYS is 0 bytes.
//The size of hiberfil.sys is 1072775168 bytes.
//The size of IO.SYS is 0 bytes.
//The size of MASK.txt is 2700 bytes.
//The size of mfc80.dll is 1093632 bytes.
//The size of mfc80u.dll is 1079808 bytes.
//The size of MSDOS.SYS is 0 bytes.
//The size of NTDETECT.COM is 47564 bytes.
//The size of ntldr is 250032 bytes.
//The size of pagefile.sys is 1610612736 bytes.
//The size of UpdatePatch.log is 22778 bytes.
//The size of UpdatePatch.txt is 30 bytes.
//The size of wt3d.ini is 234 bytes.
' The following example displays the names and sizes
' of the files in the specified directory.
Imports System.IO
Public Class FileLength
Public Shared Sub Main()
' Make a reference to a directory.
Dim di As New DirectoryInfo("c:\")
' Get a reference to each file in that directory.
Dim fiArr As FileInfo() = di.GetFiles()
' Display the names and sizes of the files.
Dim f As FileInfo
Console.WriteLine("The directory {0} contains the following files:", di.Name)
For Each f In fiArr
Console.WriteLine("The size of {0} is {1} bytes.", f.Name, f.Length)
Next f
End Sub
End Class
'This code produces output similar to the following;
'results may vary based on the computer/file structure/etc.:
'
'The directory c:\ contains the following files:
'The size of MyComputer.log is 274 bytes.
'The size of AUTOEXEC.BAT is 0 bytes.
'The size of boot.ini is 211 bytes.
'The size of CONFIG.SYS is 0 bytes.
'The size of hiberfil.sys is 1072775168 bytes.
'The size of IO.SYS is 0 bytes.
'The size of MASK.txt is 2700 bytes.
'The size of mfc80.dll is 1093632 bytes.
'The size of mfc80u.dll is 1079808 bytes.
'The size of MSDOS.SYS is 0 bytes.
'The size of NTDETECT.COM is 47564 bytes.
'The size of ntldr is 250032 bytes.
'The size of pagefile.sys is 1610612736 bytes.
'The size of UpdatePatch.log is 22778 bytes.
'The size of UpdatePatch.txt is 30 bytes.
'The size of wt3d.ini is 234 bytes.
Commenti
Il valore della Length proprietà viene pre-memorizzato nella cache se l'istanza corrente dell'oggetto FileInfo è stata restituita da uno dei metodi seguenti DirectoryInfo :
Per ottenere il valore più recente, chiamare il Refresh metodo .