A C# Http Multipart/form-data parser that works correctly on binary data and very large files.
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$ dotnet add package HttpMultipartParserReadme
Http Multipart Parser
A C# Http Multipart/form-data parser that works correctly on binary data and very large files.
$ dotnet add package HttpMultipartParser
| Release Notes | NuGet (stable) | MyGet (prerelease) |
|---|
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The Http Multipart Parser does it exactly what it claims on the tin: parses multipart/form-data. This particular parser is well suited to parsing large data from streams as it doesn't attempt to read the entire stream at once and procudes a set of streams for file data.
The easiest way to include HttpMultipartParser in your project is by adding the nuget package to your project:
PM> Install-Package HttpMultipartParser
.NET Standard 2.1 (which includes .NET 5.0 and all subsequent versions as well as some legacy versions such as .NET Core 3.x and ASP.NET Core 3.x).MultipartFormDataParser.Parse (or it's asynchronous counterpart MultipartFormDataParser.ParseAsync).parser.Run() (or it's asynchronous counterpart parser.RunAsync())// stream:
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Content-Disposition: form-data; name="username"
example
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Content-Disposition: form-data; name="email"
example@data.com
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Content-Disposition: form-data; name="files[]"; filename="photo1.jpg"
Content-Type: image/jpeg
ExampleBinaryData012031203
-----------------------------41952539122868--
// ===== Simple Parsing ====
// You can parse synchronously:
var parser = MultipartFormDataParser.Parse(stream);
// Or you can parse asynchronously:
var parser = await MultipartFormDataParser.ParseAsync(stream).ConfigureAwait(false);
// From this point the data is parsed, we can retrieve the
// form data using the GetParameterValue method.
var username = parser.GetParameterValue("username");
var email = parser.GetParameterValue("email");
// Files are stored in a list:
var file = parser.Files.First();
string filename = file.FileName;
Stream data = file.Data;
// ==== Advanced Parsing ====
var parser = new StreamingMultipartFormDataParser(stream);
parser.ParameterHandler += parameter => DoSomethingWithParameter(parameter);
parser.FileHandler += (name, fileName, type, disposition, buffer, bytes, partNumber, additionalProperties) =>
{
// Write the part of the file we've received to a file stream. (Or do something else)
filestream.Write(buffer, 0, bytes);
};
// You can parse synchronously:
parser.Run();
// Or you can parse asynchronously:
await parser.RunAsync().ConfigureAwait(false);// stream:
-----------------------------41952539122868
Content-Disposition: form-data; name="checkbox"
likes_cake
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Content-Disposition: form-data; name="checkbox"
likes_cookies
-----------------------------41952539122868--
// ===== Simple Parsing ====
// You can parse synchronously:
var parser = MultipartFormDataParser.Parse(stream);
// Or you can parse asynchronously:
var parser = await MultipartFormDataParser.ParseAsync(stream).ConfigureAwait(false);
// From this point the data is parsed, we can retrieve the
// form data from the GetParameterValues method
var checkboxResponses = parser.GetParameterValues("checkbox");
foreach(var parameter in checkboxResponses)
{
Console.WriteLine("Parameter {0} is {1}", parameter.Name, parameter.Data)
}// stream:
-----------------------------41111539122868
Content-Disposition: form-data; name="files[]"; filename="photo1.jpg"
Content-Type: image/jpeg
MoreBinaryData
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Content-Disposition: form-data; name="files[]"; filename="photo2.jpg"
Content-Type: image/jpeg
ImagineLotsOfBinaryData
-----------------------------41111539122868--
// ===== Simple Parsing ====
// You can parse synchronously:
var parser = MultipartFormDataParser.Parse(stream);
// Or you can parse asynchronously:
var parser = await MultipartFormDataParser.ParseAsync(stream).ConfigureAwait(false);
// Loop through all the files
foreach(var file in parser.Files)
{
Stream data = file.Data;
// Do stuff with the data.
}
// ==== Advanced Parsing ====
var parser = new StreamingMultipartFormDataParser(stream);
parser.ParameterHandler += parameter => DoSomethingWithParameter(parameter);
parser.FileHandler += (name, fileName, type, disposition, buffer, bytes, partNumber, additionalProperties) =>
{
// Write the part of the file we've received to a file stream. (Or do something else)
// Assume that filesreamsByName is a Dictionary<string, FileStream> of all the files
// we are writing.
filestreamsByName[name].Write(buffer, 0, bytes);
};
parser.StreamClosedHandler += ()
{
// Do things when my input stream is closed
};
// You can parse synchronously:
parser.Run();
// Or you can parse asynchronously:
await parser.RunAsync().ConfigureAwait(false);This project is licensed under MIT.