Hi,
I am working on a small application that uses a WebClient to download an XML file via an API call.
Just downloading the file is fine, that all works but I really wanted some way to show the download progress to the end user.
Searching on the net I found a small application which shows a Download ProgressBar during the download of a file, brilliant I thought, that will do it.
Having run this app, it does work fine when downloading a regular file from a regular URL but will not work when I enter my API call URL. It throws an exception because there are illegal characters in the filename.
Here is the code of the small app:-
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.IO;
namespace DownloadProgressBar1
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void backgroundWorker1_DoWork(object sender, DoWorkEventArgs e)
{
// the URL to download the file from
string sUrlToReadFileFrom = textBoxSourceFile.Text;
// the path to write the file to
int iLastIndex = sUrlToReadFileFrom.LastIndexOf('/');
string sDownloadFileName = sUrlToReadFileFrom.Substring(iLastIndex + 1, (sUrlToReadFileFrom.Length - iLastIndex - 1));
string sFilePathToWriteFileTo = textBoxDestinationFolder.Text + "\\" + sDownloadFileName;
// first, we need to get the exact size (in bytes) of the file we are downloading
Uri url = new Uri(sUrlToReadFileFrom);
System.Net.HttpWebRequest request = (System.Net.HttpWebRequest)System.Net.WebRequest.Create(url);
System.Net.HttpWebResponse response = (System.Net.HttpWebResponse)request.GetResponse();
response.Close();
// gets the size of the file in bytes
Int64 iSize = response.ContentLength;
// keeps track of the total bytes downloaded so we can update the progress bar
Int64 iRunningByteTotal = 0;
// use the webclient object to download the file
using (System.Net.WebClient client = new System.Net.WebClient())
{
// open the file at the remote URL for reading
using (System.IO.Stream streamRemote = client.OpenRead(new Uri(sUrlToReadFileFrom)))
{
// using the FileStream object, we can write the downloaded bytes to the file system
using (Stream streamLocal = new FileStream(sFilePathToWriteFileTo, FileMode.Create, FileAccess.Write, FileShare.None))
{
// loop the stream and get the file into the byte buffer
int iByteSize = 0;
byte[] byteBuffer = new byte[iSize];
while ((iByteSize = streamRemote.Read(byteBuffer, 0, byteBuffer.Length)) > 0)
{
// write the bytes to the file system at the file path specified
streamLocal.Write(byteBuffer, 0, iByteSize);
iRunningByteTotal += iByteSize;
// calculate the progress out of a base "100"
double dIndex = (double)(iRunningByteTotal);
double dTotal = (double)byteBuffer.Length;
double dProgressPercentage = (dIndex / dTotal);
int iProgressPercentage = (int)(dProgressPercentage * 100);
// update the progress bar
backgroundWorker1.ReportProgress(iProgressPercentage);
}
// clean up the file stream
streamLocal.Close();
}
// close the connection to the remote server
streamRemote.Close();
}
}
}
private void backgroundWorker1_ProgressChanged(object sender, ProgressChangedEventArgs e)
{
progressBar1.Value = e.ProgressPercentage;
}
private void backgroundWorker1_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
{
MessageBox.Show("File download complete");
}
private void btnTestDownload_Click(object sender, EventArgs e)
{
if (textBoxSourceFile.Text.Length == 0)
{
MessageBox.Show("Please enter a source file");
return;
}
if (textBoxDestinationFolder.Text.Length == 0)
{
MessageBox.Show("Please enter a destination file");
}
backgroundWorker1.RunWorkerAsync();
}
}
}An example of the API call that I am making is below, it returns the value in XML format.
I have 'xxxx'd out private info for security reasons.
Any pointers to getting this to work would be appreciated, or an alternative where I could just show a loading.gif while the file is being downloaded, would be greatly appreciated.
Kind regards..,
MT