Using RestSharp to Download a File
RestSharp is a popular library for making HTTP requests in C# and Here, we'll show you two of the best ways to download a file using RestSharp.
1. Downloading File Directly to Disk
We can download a file directly to disk using RestSharp's DownloadData method. This approach is suitable when we want to save the file directly to disk without loading it into memory.
using RestSharp;
public void DownloadFileToDisk(string fileUrl, string destinationFilePath)
{
// Create a RestClient instance
var client = new RestClient(fileUrl);
// Create a RestRequest instance
var request = new RestRequest(Method.GET);
// Execute the request and save the response to disk
client.DownloadData(request).SaveAs(destinationFilePath);
}
2. Downloading File to Memory Stream
If we want to download a file to a memory stream instead of saving it directly to disk, we can use RestSharp's DownloadData method with a MemoryStream. This approach is useful when we need to further process the file in memory.
using RestSharp;
using System.IO;
public MemoryStream DownloadFileToMemory(string fileUrl)
{
// Create a RestClient instance
var client = new RestClient(fileUrl);
// Create a RestRequest instance
var request = new RestRequest(Method.GET);
// Execute the request and save the response to a MemoryStream
byte[] fileBytes = client.DownloadData(request);
return new MemoryStream(fileBytes);
}
Downloading CSV & Excel Files with RestSharp
When it comes to downloading CSV and Excel files using RestSharp, we can follow a similar approach as we did for downloading a file.
1. Downloading CSV File
To download a CSV file, we'll use RestSharp's DownloadData method to retrieve the file content as a byte array. Then, we'll save the byte array to a file with the .csv extension.
using RestSharp;
using System.IO;
public class CsvDownloader
{
public void DownloadCsv(string csvUrl, string destinationFilePath)
{
// Create a RestClient instance
var client = new RestClient(csvUrl);
// Create a RestRequest instance with GET method
var request = new RestRequest(Method.GET);
// Download the CSV file as a byte array
byte[] csvBytes = client.DownloadData(request);
// Save the byte array to a file with .csv extension
File.WriteAllBytes(destinationFilePath, csvBytes);
}
}
2. Downloading Excel File
Similarly, to download an Excel file, we'll use RestSharp's DownloadData method to retrieve the file content as a byte array. Then, we'll save the byte array to a file with the .xlsx extension.
using RestSharp;
using System.IO;
public class ExcelDownloader
{
public void DownloadExcel(string excelUrl, string destinationFilePath)
{
// Create a RestClient instance
var client = new RestClient(excelUrl);
// Create a RestRequest instance with GET method
var request = new RestRequest(Method.GET);
// Download the Excel file as a byte array
byte[] excelBytes = client.DownloadData(request);
// Save the byte array to a file with .xlsx extension
File.WriteAllBytes(destinationFilePath, excelBytes);
}
}
Downloading a PDF with RestSharp
When we need to download a PDF file using RestSharp, we follow a straightforward process. Here's how we can do it:
1. Create a RestClient Instance
We start by creating an instance of the RestClient class, specifying the URL of the PDF file we want to download.
using RestSharp;
var client = new RestClient("pdf-url-here");
2. Create a RestRequest Instance
Next, we create a RestRequest instance with the HTTP method set to GET, as we are fetching the PDF file from the server.
var request = new RestRequest(Method.GET);
3. Download the PDF File
Now, we use RestSharp's DownloadData method to download the PDF file content as a byte array.
byte[] pdfBytes = client.DownloadData(request);
4. Save the PDF File
Finally, we save the byte array to a file with the .pdf extension, completing the download process.
System.IO.File.WriteAllBytes("destination-path.pdf", pdfBytes);
With these steps, we can easily download a PDF file using RestSharp in our C# application.
Using RestSharp to Download a File (Async Version)
RestSharp also supports asynchronous operations, allowing us to download files asynchronously. Here are the async versions of the previous methods:
1. Downloading File Directly to Disk (Async)
We can download a file directly to disk asynchronously using RestSharp's DownloadDataAsync method.
using RestSharp;
using System.Threading.Tasks;
public async Task DownloadFileToDiskAsync(string fileUrl, string destinationFilePath)
{
// Create a RestClient instance
var client = new RestClient(fileUrl);
// Create a RestRequest instance
var request = new RestRequest(Method.GET);
// Execute the request asynchronously and save the response to disk
byte[] fileBytes = await client.DownloadDataTaskAsync(request);
await Task.Run(() => File.WriteAllBytes(destinationFilePath, fileBytes));
}
2. Downloading File to Memory Stream (Async)
We can also download a file to a memory stream asynchronously using RestSharp's DownloadDataAsync method.
using RestSharp;
using System.IO;
using System.Threading.Tasks;
public async Task<MemoryStream> DownloadFileToMemoryAsync(string fileUrl)
{
// Create a RestClient instance
var client = new RestClient(fileUrl);
// Create a RestRequest instance
var request = new RestRequest(Method.GET);
// Execute the request asynchronously and save the response to a MemoryStream
byte[] fileBytes = await client.DownloadDataTaskAsync(request);
return new MemoryStream(fileBytes);
}