WebClient.DownloadFile Method

Definition

Namespace:

System.Net

Assembly:

System.Net.WebClient.dll

Downloads the resource with the specified URI to a local file.

Overloads

DownloadFile(Uri, String)	Downloads the resource with the specified URI to a local file.
DownloadFile(String, String)	Downloads the resource with the specified URI to a local file.

DownloadFile(Uri, String)

Source:

WebClient.cs

Downloads the resource with the specified URI to a local file.

public:
 void DownloadFile(Uri ^ address, System::String ^ fileName);

public void DownloadFile (Uri address, string fileName);

member this.DownloadFile : Uri * string -> unit

Public Sub DownloadFile (address As Uri, fileName As String)

Parameters

address

Uri

The URI specified as a String, from which to download data.

fileName

String

The name of the local file that is to receive the data.

Exceptions

ArgumentNullException

The address parameter is null.

-or-

The fileName parameter is null.

WebException

The URI formed by combining BaseAddress and address is invalid.

-or-

filename is null or Empty.

-or-

The file does not exist.

-or-

An error occurred while downloading data.

NotSupportedException

The method has been called simultaneously on multiple threads.

Remarks

Caution

WebRequest, HttpWebRequest, ServicePoint, and WebClient are obsolete, and you shouldn't use them for new development. Use HttpClient instead.

The DownloadFile method downloads to a local file data from the URI specified by in the address parameter. This method blocks while downloading the resource. To download a resource and continue executing while waiting for the server's response, use one of the DownloadFileAsync methods.

If the BaseAddress property is not an empty string ("") and address does not contain an absolute URI, address must be a relative URI that is combined with BaseAddress to form the absolute URI of the requested data. If the QueryString property is not an empty string, it is appended to address.

This method uses the RETR command to download an FTP resource. For an HTTP resource, the GET method is used.

Note

This member outputs trace information when you enable network tracing in your application. For more information, see Network Tracing in .NET Framework.

When using this method in a middle tier application, such as an ASP.NET page, you will receive an error if the account under which the application executes does not have permission to access the file.

DownloadFile(String, String)

Source:

WebClient.cs

Downloads the resource with the specified URI to a local file.

public:
 void DownloadFile(System::String ^ address, System::String ^ fileName);

public void DownloadFile (string address, string fileName);

member this.DownloadFile : string * string -> unit

Public Sub DownloadFile (address As String, fileName As String)

Parameters

address

String

The URI from which to download data.

fileName

String

The name of the local file that is to receive the data.

Exceptions

ArgumentNullException

The address parameter is null.

WebException

The URI formed by combining BaseAddress and address is invalid.

-or-

filename is null or Empty.

-or-

The file does not exist.

-or- An error occurred while downloading data.

NotSupportedException

The method has been called simultaneously on multiple threads.

Examples

The following code example downloads a file from http://www.contoso.com to the local hard drive.

String^ remoteUri = "http://www.contoso.com/library/homepage/images/";
String^ fileName = "ms-banner.gif", ^myStringWebResource = nullptr;
// Create a new WebClient instance.
WebClient^ myWebClient = gcnew WebClient;
// Concatenate the domain with the Web resource filename.
myStringWebResource = String::Concat( remoteUri, fileName );
Console::WriteLine( "Downloading File \"{0}\" from \"{1}\" .......\n\n", fileName, myStringWebResource );
// Download the Web resource and save it into the current filesystem folder.
myWebClient->DownloadFile( myStringWebResource, fileName );
Console::WriteLine( "Successfully Downloaded File \"{0}\" from \"{1}\"", fileName, myStringWebResource );
Console::WriteLine( "\nDownloaded file saved in the following file system folder:\n\t {0}", Application::StartupPath );

string remoteUri = "http://www.contoso.com/library/homepage/images/";
string fileName = "ms-banner.gif", myStringWebResource = null;
// Create a new WebClient instance.
WebClient myWebClient = new WebClient();
// Concatenate the domain with the Web resource filename.
myStringWebResource = remoteUri + fileName;
Console.WriteLine("Downloading File \"{0}\" from \"{1}\" .......\n\n", fileName, myStringWebResource);
// Download the Web resource and save it into the current filesystem folder.
myWebClient.DownloadFile(myStringWebResource,fileName);		
Console.WriteLine("Successfully Downloaded File \"{0}\" from \"{1}\"", fileName, myStringWebResource);
Console.WriteLine("\nDownloaded file saved in the following file system folder:\n\t" + Application.StartupPath);

Dim remoteUri As String = "http://www.contoso.com/library/homepage/images/"
Dim fileName As String = "ms-banner.gif"
Dim myStringWebResource As String = Nothing
' Create a new WebClient instance.
Dim myWebClient As New WebClient()
' Concatenate the domain with the Web resource filename. Because DownloadFile 
'requires a fully qualified resource name, concatenate the domain with the Web resource file name.
myStringWebResource = remoteUri + fileName
Console.WriteLine("Downloading File ""{0}"" from ""{1}"" ......." + ControlChars.Cr + ControlChars.Cr, fileName, myStringWebResource)
' The DownloadFile() method downloads the Web resource and saves it into the current file-system folder.
myWebClient.DownloadFile(myStringWebResource, fileName)
Console.WriteLine("Successfully Downloaded file ""{0}"" from ""{1}""", fileName, myStringWebResource)
Console.WriteLine((ControlChars.Cr + "Downloaded file saved in the following file system folder:" + ControlChars.Cr + ControlChars.Tab + Application.StartupPath))

Remarks

Caution

WebRequest, HttpWebRequest, ServicePoint, and WebClient are obsolete, and you shouldn't use them for new development. Use HttpClient instead.

The DownloadFile method downloads to a local file data from the URI specified by in the address parameter. This method blocks while downloading the resource. To download a resource and continue executing while waiting for the server's response, use one of the DownloadFileAsync methods.

If the BaseAddress property is not an empty string ("") and address does not contain an absolute URI, address must be a relative URI that is combined with BaseAddress to form the absolute URI of the requested data. If the QueryString property is not an empty string, it is appended to address.

This method uses the RETR command to download an FTP resource. For an HTTP resource, the GET method is used.

Note

This member outputs trace information when you enable network tracing in your application. For more information, see Network Tracing in .NET Framework.

When using this method in a middle tier application, such as an ASP.NET page, you will receive an error if the account under which the application executes does not have permission to access the file.