C# Signature:
/// <summary>
/// The URLMON library contains this function, URLDownloadToFile, which is a way
/// to download files without user prompts. The ExecWB( _SAVEAS ) function always
/// prompts the user, even if _DONTPROMPTUSER parameter is specified, for "internet
/// security reasons". This function gets around those reasons.
/// </summary>
/// <param name="pCaller">Pointer to caller object (AX).</param>
/// <param name="szURL">String of the URL.</param>
/// <param name="szFileName">String of the destination filename/path.</param>
/// <param name="dwReserved">[reserved].</param>
/// <param name="lpfnCB">A callback function to monitor progress or abort.</param>
/// <returns>0 for okay.</returns>
[DllImport("urlmon.dll", CharSet=CharSet.Auto, SetLastError=true)]
static extern Int32 URLDownloadToFile(
[MarshalAs(UnmanagedType.IUnknown)] object pCaller,
[MarshalAs(UnmanagedType.LPWStr)] string szURL,
[MarshalAs(UnmanagedType.LPWStr)] string szFileName,
Int32 dwReserved,
IntPtr lpfnCB);
// This version maps HRESULT to exception:
[DllImport("urlmon.dll", CharSet=CharSet.Auto, PreserveSig=false)]
private static extern void URLDownloadToFile(
[MarshalAs(UnmanagedType.IUnknown)] object pCaller,
[MarshalAs(UnmanagedType.LPTStr)] string szURL,
[MarshalAs(UnmanagedType.LPTStr)] string szFileName,
Int32 dwReserved,
IntPtr lpfnCB);
VB Signature:
Declare Function URLDownloadToFile Lib "urlmon.dll" (TODO) As TODO
User-Defined Types:
None.
Notes:
This function does not prompt user for file location, as does ExecWB (even when you specify DONTPROMPT), and it does not return until file transfer finishes or fails.
http://www.pinvoke.net/default.aspx/urlmon/URLDownloadToFile%20.html
Tips & Tricks:
Please add some!
Sample Code:
int response = URLDownloadToFile( null, urlStr, fileToStoreStr, 0, IntPtr.Zero );
// For the second version:
URLDownloadToFile(IE as SHDocVw.IWebBrowser2, urlStr, fileToStoreStr, 0, IntPtr.Zero );
Alternative Managed API:
Do you know one? Please contribute it!
In VB.Net it's very simple to download a file (use asynchronous pattern from C# example if needed):
If (My.Computer.Network.IsAvailable) Then
My.Computer.Network.DownloadFile("http://www.pinvoke.net/", "C:\Temp\pinvoke.htm")
Else
MsgBox("Network not found!")
End If
