Blazor download files to the browser from c# without any JavaScript library or dependency.
BlazorDownloadFile is the solution to saving files on the client-side, and is perfect for web apps that generates files on the client.
However if the file is coming from the server we recommend you to first try to use Content-Disposition attachment response header as it has more cross-browser compatibility.
Install-Package BlazorDownloadFile -Version 2.4.0.2
services.AddBlazorDownloadFile(ServiceLifetime lifetime = ServiceLifetime.Scoped);
Note: ServiceLifetime.Singleton is not supported.
If you are using Content-Security-Policy "script-src 'self'" then you need to add the script manually:
[Inject] IBlazorDownloadFileService BlazorDownloadFileService { get; set; }
AddBuffer
// Adds a buffer to the javascript side ValueTask AddBuffer(string bytesBase64); | Parameter | Type | Description |
|---|---|---|
bytesBase64 | string | The base 64 string |
AddBuffer
// Adds a buffer to the javascript side ValueTask AddBuffer(string bytesBase64, CancellationToken cancellationToken); | Parameter | Type | Description |
|---|---|---|
bytesBase64 | string | The base 64 string |
cancellationToken | CancellationToken | The cancellation token |
AddBuffer
// Adds a buffer to the javascript side ValueTask AddBuffer(string bytesBase64, TimeSpan timeOut) | Parameter | Type | Description |
|---|---|---|
bytesBase64 | string | The base 64 string |
timeOut | TimeSpan | The timeout |
AddBuffer
// Adds a buffer to javascript side ValueTask AddBuffer(byte[] bytes); | Parameter | Type | Description |
|---|---|---|
bytes | byte[] | The bytes |
AddBuffer
// Adds a buffer to javascript side ValueTask AddBuffer(byte[] bytes, CancellationToken cancellationToken); | Parameter | Type | Description |
|---|---|---|
bytes | byte[] | The bytes |
cancellationToken | CancellationToken | The cancellation token |
AddBuffer
// Adds a buffer to javascript side ValueTask AddBuffer(byte[] bytes, TimeSpan timeOut); | Parameter | Type | Description |
|---|---|---|
bytes | byte[] | The bytes |
timeOut | TimeSpan | The timeout |
AddBuffer
// Adds a buffer to javascript side ValueTask AddBuffer(IEnumerable<byte> bytes); | Parameter | Type | Description |
|---|---|---|
bytes | IEnumerable<byte> | The bytes |
AddBuffer
// Adds a buffer to javascript side ValueTask AddBuffer(IEnumerable<byte> bytes, CancellationToken cancellationToken); | Parameter | Type | Description |
|---|---|---|
bytes | IEnumerable<byte> | The bytes |
cancellationToken | CancellationToken | The cancellation token |
AddBuffer
// Adds a buffer to javascript side ValueTask AddBuffer(IEnumerable<byte> bytes, TimeSpan timeOut); | Parameter | Type | Description |
|---|---|---|
bytes | IEnumerable<byte> | The bytes |
timeOut | TimeSpan | The timeout |
AddBuffer
// Adds a buffer to javascript side ValueTask AddBuffer(Stream stream); | Parameter | Type | Description |
|---|---|---|
stream | Stream | The stream |
AddBuffer
// Adds a buffer to javascript side ValueTask AddBuffer(Stream stream, CancellationToken cancellationToken); | Parameter | Type | Description |
|---|---|---|
stream | Stream | The stream |
cancellationToken | CancellationToken | The cancellation token |
AddBuffer
// Adds a buffer to javascript side ValueTask AddBuffer(Stream stream, CancellationToken streamReadcancellationToken, TimeSpan timeOutJavaScript); | Parameter | Type | Description |
|---|---|---|
stream | Stream | The stream |
streamReadcancellationToken | CancellationToken | The cancellation token |
timeOutJavaScript | TimeSpan | The timeout |
AnyBuffer
// Checks wether there is any buffer loaded in the JavaScript side. ValueTask<bool> AnyBuffer(); BuffersCount
// Gets the buffers count loaded in the JavaScript side. ValueTask<int> BuffersCount(); ClearBuffers
// Clears the buffers in javascript side ValueTask ClearBuffers(); DownloadBase64Buffers
// Merges and downloads all pending buffers into a single file in the browser. This method should be called when the added buffers where a base64 string type. ValueTask<DownloadFileResult> DownloadBase64Buffers(string fileName, string contentType = "application/octet-stream"); | Parameter | Type | Description |
|---|---|---|
fileName | string | The filename |
contentType | string | The content type |
DownloadBase64Buffers
// Merges and downloads all pending buffers into a single file in the browser. This method should be called when the added buffers where a base64 string type. ValueTask<DownloadFileResult> DownloadBase64Buffers(string fileName, CancellationToken cancellationToken, string contentType = "application/octet-stream"); | Parameter | Type | Description |
|---|---|---|
fileName | string | The filename |
cancellationToken | CancellationToken | The cancellation token |
contentType | string | The content type |
DownloadBase64Buffers
// Merges and downloads all pending buffers into a single file in the browser. This method should be called when the added buffers where a base64 string type. ValueTask<DownloadFileResult> DownloadBase64Buffers(string fileName, TimeSpan timeOut, string contentType = "application/octet-stream"); | Parameter | Type | Description |
|---|---|---|
fileName | string | The filename |
timeOut | TimeSpan | The timeout |
contentType | string | The content type |
DownloadBinaryBuffers
// Merges and downloads all pending buffers into a single file in the browser. This method should be called when the added buffers where a byte array, byte enumerable or a stream types. ValueTask<DownloadFileResult> DownloadBinaryBuffers(string fileName, string contentType = "application/octet-stream"); | Parameter | Type | Description |
|---|---|---|
fileName | string | The filename |
contentType | string | The content type |
DownloadBinaryBuffers
// Merges and downloads all pending buffers into a single file in the browser. This method should be called when the added buffers where a byte array, byte enumerable or a stream types. ValueTask<DownloadFileResult> DownloadBinaryBuffers(string fileName, CancellationToken cancellationToken, string contentType = "application/octet-stream"); | Parameter | Type | Description |
|---|---|---|
fileName | string | The filename |
cancellationToken | CancellationToken | The cancellation token |
contentType | string | The content type |
DownloadBinaryBuffers
// Merges and downloads all pending buffers into a single file in the browser. This method should be called when the added buffers where a byte array, byte enumerable or a stream types. ValueTask<DownloadFileResult> DownloadBinaryBuffers(string fileName, TimeSpan timeOut, string contentType = "application/octet-stream"); | Parameter | Type | Description |
|---|---|---|
fileName | string | The filename |
timeOut | TimeSpan | The timeout |
contentType | string | The content type |
DownloadFile
// Download a file from blazor context to the browser ValueTask<DownloadFileResult> DownloadFile(string fileName, string bytesBase64, string contentType = "application/octet-stream"); | Parameter | Type | Description |
|---|---|---|
fileName | string | The filename |
bytesBase64 | string | The bytes base 64 of the file |
contentType | string | The file content type |
DownloadFile
// Download a file from blazor context to the browser ValueTask<DownloadFileResult> DownloadFile(string fileName, string bytesBase64, CancellationToken cancellationToken, string contentType = "application/octet-stream"); | Parameter | Type | Description |
|---|---|---|
fileName | string | The filename |
bytesBase64 | string | The bytes base 64 of the file |
cancellationToken | CancellationToken | The cancellation token |
contentType | string | The file content type |
DownloadFile
// Download a file from blazor context to the browser ValueTask<DownloadFileResult> DownloadFile(string fileName, string bytesBase64, TimeSpan timeOut, string contentType = "application/octet-stream"); | Parameter | Type | Description |
|---|---|---|
fileName | string | The filename |
bytesBase64 | string | The bytes base 64 of the file |
timeOut | TimeSpan | The timeout |
contentType | string | The file content type |
DownloadFile
// Download a file from blazor context to the browser ValueTask<DownloadFileResult> DownloadFile(string fileName, byte[] bytes, string contentType = "application/octet-stream"); | Parameter | Type | Description |
|---|---|---|
fileName | string | The filename |
bytes | byte[] | The bytes of the file |
contentType | string | The file content type |
DownloadFile
// Download a file from blazor context to the browser ValueTask<DownloadFileResult> DownloadFile(string fileName, byte[] bytes, CancellationToken cancellationToken, string contentType = "application/octet-stream"); | Parameter | Type | Description |
|---|---|---|
fileName | string | The filename |
bytes | byte[] | The bytes of the file |
cancellationToken | CancellationToken | The cancellation token |
contentType | string | The file content type |
DownloadFile
// Download a file from blazor context to the browser ValueTask<DownloadFileResult> DownloadFile(string fileName, byte[] bytes, TimeSpan timeOut, string contentType = "application/octet-stream"); | Parameter | Type | Description |
|---|---|---|
fileName | string | The filename |
bytes | byte[] | The bytes of the file |
timeOut | TimeSpan | The timeout |
contentType | string | The file content type |
DownloadFile
// Download a file from blazor context to the browser ValueTask<DownloadFileResult> DownloadFile(string fileName, IEnumerable<byte> bytes, string contentType = "application/octet-stream"); | Parameter | Type | Description |
|---|---|---|
fileName | string | The filename |
bytes | IEnumerable<byte> | The bytes of the file |
contentType | string | The file content type |
DownloadFile
// Download a file from blazor context to the browser ValueTask<DownloadFileResult> DownloadFile(string fileName, IEnumerable<byte> bytes, CancellationToken cancellationToken, string contentType = "application/octet-stream"); | Parameter | Type | Description |
|---|---|---|
fileName | string | The filename |
bytes | IEnumerable<byte> | The bytes of the file |
cancellationToken | CancellationToken | The cancellation token |
contentType | string | The file content type |
DownloadFile
// Download a file from blazor context to the browser ValueTask<DownloadFileResult> DownloadFile(string fileName, IEnumerable<byte> bytes, TimeSpan timeOut, string contentType = "application/octet-stream"); | Parameter | Type | Description |
|---|---|---|
fileName | string | The filename |
bytes | IEnumerable<byte> | The bytes of the file |
timeOut | TimeSpan | The timeout |
contentType | string | The file content type |
DownloadFile
// Download a file from blazor context to the browser ValueTask<DownloadFileResult> DownloadFile(string fileName, Stream stream, string contentType = "application/octet-stream"); | Parameter | Type | Description |
|---|---|---|
fileName | string | The filename |
stream | Stream | The stream of the file |
contentType | string | The file content type |
DownloadFile
// Download a file from blazor context to the browser ValueTask<DownloadFileResult> DownloadFile(string fileName, Stream stream, CancellationToken cancellationTokenBytesRead, CancellationToken cancellationTokenJavaScriptInterop, string contentType = "application/octet-stream"); | Parameter | Type | Description |
|---|---|---|
fileName | string | The filename |
stream | Stream | The stream of the file |
cancellationTokenBytesRead | CancellationToken | The cancellation token when reading bytes |
cancellationTokenJavaScriptInterop | CancellationToken | The cancellation token when executing javascript |
contentType | string | The file content type |
DownloadFile
// Download a file from blazor context to the browser ValueTask<DownloadFileResult> DownloadFile(string fileName, Stream stream, CancellationToken cancellationTokenBytesRead, TimeSpan timeOutJavaScriptInterop, string contentType = "application/octet-stream"); | Parameter | Type | Description |
|---|---|---|
fileName | string | The filename |
stream | Stream | The stream of the file |
cancellationTokenBytesRead | CancellationToken | The cancellation token when reading bytes |
timeOutJavaScriptInterop | TimeSpan | The timeout when executing javascript |
contentType | string | The file content type |
DownloadFile
// Download a file from blazor context to the browser ValueTask<DownloadFileResult> DownloadFileFromText(string fileName, string plainText, Encoding encoding, string contentType = "text/plain", bool encoderShouldEmitIdentifier = false); | Parameter | Type | Description |
|---|---|---|
fileName | string | The filename |
plainText | string | The stream of the file |
encoding | Encoding | The encoding to use |
contentType | string | The file content type |
encoderShouldEmitIdentifier | bool | true to specify that the System.Text.Encoding.GetPreamble method returns a Unicode byte order mark |
DownloadFile
// Download a file from blazor context to the browser ValueTask<DownloadFileResult> DownloadFileFromText(string fileName, string plainText, Encoding encoding, CancellationToken cancellationToken, string contentType = "text/plain", bool encoderShouldEmitIdentifier = false); | Parameter | Type | Description |
|---|---|---|
fileName | string | The filename |
plainText | string | The stream of the file |
encoding | Encoding | The encoding to use |
cancellationToken | CancellationToken | The cancellation token |
contentType | string | The file content type |
encoderShouldEmitIdentifier | bool | true to specify that the System.Text.Encoding.GetPreamble method returns a Unicode byte order mark |
DownloadFile
// Download a file from blazor context to the browser ValueTask<DownloadFileResult> DownloadFileFromText(string fileName, string plainText, Encoding encoding, TimeSpan timeOut, string contentType = "text/plain", bool encoderShouldEmitIdentifier = false); | Parameter | Type | Description |
|---|---|---|
fileName | string | The filename |
plainText | string | The stream of the file |
encoding | Encoding | The encoding to use |
timeOut | TimeSpan | The timeout |
contentType | string | The file content type |
encoderShouldEmitIdentifier | bool | true to specify that the System.Text.Encoding.GetPreamble method returns a Unicode byte order mark |
DownloadFile
// Download a file from blazor context to the browser ValueTask<DownloadFileResult> DownloadFile(string fileName, string bytesBase64, int bufferSize = 32768, string contentType = "application/octet-stream", IProgress<double>? progress = null); | Parameter | Type | Description |
|---|---|---|
fileName | string | The filename |
bytesBase64 | string | The bytes base 64 of the file |
bufferSize | int | The buffer size |
contentType | string | The file content type |
progress | IProgress<double>? | The progress percent of data transferred |
DownloadFile
// Download a file from blazor context to the browser ValueTask<DownloadFileResult> DownloadFile(string fileName, string bytesBase64, CancellationToken cancellationToken, int bufferSize = 32768, string contentType = "application/octet-stream", IProgress<double>? progress = null); | Parameter | Type | Description |
|---|---|---|
fileName | string | The filename |
bytesBase64 | string | The bytes base 64 of the file |
cancellationToken | CancellationToken | The cancellation token |
bufferSize | int | The buffer size |
contentType | string | The file content type |
progress | IProgress<double>? | The progress percent of data transferred |
DownloadFile
// Download a file from blazor context to the browser ValueTask<DownloadFileResult> DownloadFile(string fileName, string bytesBase64, TimeSpan timeOut, int bufferSize = 32768, string contentType = "application/octet-stream", IProgress<double>? progress = null); | Parameter | Type | Description |
|---|---|---|
fileName | string | The filename |
bytesBase64 | string | The bytes base 64 of the file |
timeOut | TimeSpan | The timeout |
bufferSize | int | The buffer size |
contentType | string | The file content type |
progress | IProgress<double>? | The progress percent of data transferred |
DownloadFile
// Download a file from blazor context to the browser ValueTask<DownloadFileResult> DownloadFile(string fileName, byte[] bytes, int bufferSize = 32768, string contentType = "application/octet-stream", IProgress<double>? progress = null); | Parameter | Type | Description |
|---|---|---|
fileName | string | The filename |
bytes | byte[] | The bytes of the file |
bufferSize | int | The buffer size |
contentType | string | The file content type |
progress | IProgress<double>? | The progress percent of data transferred |
DownloadFile
// Download a file from blazor context to the browser ValueTask<DownloadFileResult> DownloadFile(string fileName, byte[] bytes, CancellationToken cancellationToken, int bufferSize = 32768, string contentType = "application/octet-stream", IProgress<double>? progress = null); | Parameter | Type | Description |
|---|---|---|
fileName | string | The filename |
bytes | byte[] | The bytes of the file |
cancellationToken | CancellationToken | The cancellation token |
bufferSize | int | The buffer size |
contentType | string | The file content type |
progress | IProgress<double>? | The progress percent of data transferred |
DownloadFile
// Download a file from blazor context to the browser ValueTask<DownloadFileResult> DownloadFile(string fileName, byte[] bytes, TimeSpan timeOut, int bufferSize = 32768, string contentType = "application/octet-stream", IProgress<double>? progress = null); | Parameter | Type | Description |
|---|---|---|
fileName | string | The filename |
bytes | byte[] | The bytes of the file |
timeOut | TimeSpan | The timeout |
bufferSize | int | The buffer size |
contentType | string | The file content type |
progress | IProgress<double>? | The progress percent of data transferred |
DownloadFile
// Download a file from blazor context to the browser ValueTask<DownloadFileResult> DownloadFile(string fileName, IEnumerable<byte> bytes, int bufferSize = 32768, string contentType = "application/octet-stream", IProgress<double>? progress = null); | Parameter | Type | Description |
|---|---|---|
fileName | string | The filename |
bytes | IEnumerable<byte> | The bytes of the file |
bufferSize | int | The buffer size |
contentType | string | The file content type |
progress | IProgress<double>? | The progress percent of data transferred |
DownloadFile
// Download a file from blazor context to the browser ValueTask<DownloadFileResult> DownloadFile(string fileName, IEnumerable<byte> bytes, CancellationToken cancellationToken, int bufferSize = 32768, string contentType = "application/octet-stream", IProgress<double>? progress = null); | Parameter | Type | Description |
|---|---|---|
fileName | string | The filename |
bytes | IEnumerable<byte> | The bytes of the file |
cancellationToken | CancellationToken | The cancellation token |
bufferSize | int | The buffer size |
contentType | string | The file content type |
progress | IProgress<double>? | The progress percent of data transferred |
DownloadFile
// Download a file from blazor context to the browser ValueTask<DownloadFileResult> DownloadFile(string fileName, IEnumerable<byte> bytes, TimeSpan timeOut, int bufferSize = 32768, string contentType = "application/octet-stream", IProgress<double>? progress = null); | Parameter | Type | Description |
|---|---|---|
fileName | string | The filename |
bytes | IEnumerable<byte> | The bytes of the file |
timeOut | TimeSpan | The timeout |
bufferSize | int | The buffer size |
contentType | string | The file content type |
progress | IProgress<double>? | The progress percent of data transferred |
DownloadFile
// Download a file from blazor context to the browser. Please take note that this method doesn't reset the stream position to 0. ValueTask<DownloadFileResult> DownloadFile(string fileName, Stream stream, int bufferSize = 32768, string contentType = "application/octet-stream", IProgress<double>? progress = null); | Parameter | Type | Description |
|---|---|---|
fileName | string | The filename |
stream | Stream | The bytes of the file |
bufferSize | int | The buffer size |
contentType | string | The file content type |
progress | IProgress<double>? | The progress percent of data transferred |
DownloadFile
// Download a file from blazor context to the browser. Please take note that this method doesn't reset the stream position to 0. ValueTask<DownloadFileResult> DownloadFile(string fileName, Stream stream, CancellationToken cancellationTokenBytesRead, CancellationToken cancellationTokenJavaScriptInterop, int bufferSize = 32768, string contentType = "application/octet-stream", IProgress<double>? progress = null); | Parameter | Type | Description |
|---|---|---|
fileName | string | The filename |
stream | Stream | The bytes of the file |
cancellationTokenBytesRead | CancellationToken | The cancellation token when reading bytes |
cancellationTokenJavaScriptInterop | CancellationToken | The cancellation token when executing javascript |
bufferSize | int | The buffer size |
contentType | string | The file content type |
progress | IProgress<double>? | The progress percent of data transferred |
DownloadFile
// Download a file from blazor context to the browser. Please take note that this method doesn't reset the stream position to 0. ValueTask<DownloadFileResult> DownloadFile(string fileName, Stream stream, CancellationToken cancellationTokenBytesRead, TimeSpan timeOutJavaScriptInterop, int bufferSize = 32768, string contentType = "application/octet-stream", IProgress<double>? progress = null); | Parameter | Type | Description |
|---|---|---|
fileName | string | The filename |
stream | Stream | The bytes of the file |
cancellationTokenBytesRead | CancellationToken | The cancellation token when reading bytes |
timeOutJavaScriptInterop | TimeSpan | The timeout when executing javascript |
bufferSize | int | The buffer size |
contentType | string | The file content type |
progress | IProgress<double>? | The progress percent of data transferred |
DownloadFileFromText
// Download a file from blazor context to the browser ValueTask<DownloadFileResult> DownloadFileFromText(string fileName, string plainText, Encoding encoding, int bufferSize = 32768, string contentType = "text/plain", IProgress<double>? progress = null, bool encoderShouldEmitIdentifier = false); | Parameter | Type | Description |
|---|---|---|
fileName | string | The filename |
plainText | string | The plain text |
encoding | Encoding | The encoding to use |
bufferSize | int | The buffer size |
contentType | string | The file content type |
progress | IProgress<double>? | The progress percent of data transferred |
encoderShouldEmitIdentifier | bool | true to specify that the System.Text.Encoding.GetPreamble method returns a Unicode byte order mark |
DownloadFileFromText
// Download a file from blazor context to the browser ValueTask<DownloadFileResult> DownloadFileFromText(string fileName, string plainText, Encoding encoding, CancellationToken cancellationToken, int bufferSize = 32768, string contentType = "text/plain", IProgress<double>? progress = null, bool encoderShouldEmitIdentifier = false); | Parameter | Type | Description |
|---|---|---|
fileName | string | The filename |
plainText | string | The plain text |
encoding | Encoding | The encoding to use |
cancellationToken | CancellationToken | The cancellation token |
bufferSize | int | The buffer size |
contentType | string | The file content type |
progress | IProgress<double>? | The progress percent of data transferred |
encoderShouldEmitIdentifier | bool | true to specify that the System.Text.Encoding.GetPreamble method returns a Unicode byte order mark |
DownloadFileFromText
// Download a file from blazor context to the browser ValueTask<DownloadFileResult> DownloadFileFromText(string fileName, string plainText, Encoding encoding, TimeSpan timeOut, int bufferSize = 32768, string contentType = "text/plain", IProgress<double>? progress = null, bool encoderShouldEmitIdentifier = false); | Parameter | Type | Description |
|---|---|---|
fileName | string | The filename |
plainText | string | The plain text |
encoding | Encoding | The encoding to use |
timeOut | TimeSpan | The timeout |
bufferSize | int | The buffer size |
contentType | string | The file content type |
progress | IProgress<double>? | The progress percent of data transferred |
encoderShouldEmitIdentifier | bool | true to specify that the System.Text.Encoding.GetPreamble method returns a Unicode byte order mark |
Regarding on some performance test I have done in this library is that, base64 string and byte[] performs faster than Stream always.
Since there is not direct conversion between from c# Stream to a JavaScript object its a little more expensive this task.
When its base64 this is the most simple data type to transfer and work with it.
byte[] gets transformed into base64 string when transfered to JavaScript and for some reason it won't work properly when encoding cause its base64 representation turns to be something else when going after the second partition when gets encoded to base64 string. (If anyone knows how to fix or workaround this make a pull request)
Based on the las sentence, a list of bytes gets passed down from c# to JavaScript as an array of intergers with the bytes representation on JavaScript and this is the reason why I send a IList<byte> rather than byte[] internally to JavaScript.
The binary representation seems to perform very well since we just needed to call Uint8Array and push the binary representation entirely into the array to then pass it down to the JavaScript native Blob object.
Take note that you may use the overload methods with buffers if you are sending big files over the wire and also that browsers have their own limitations on JavaScript Max Blob Size based on the device hardware, browser vendor and the OS.
Take note also that blazor server side uses Signal R and has its data transfer (buffer) limitations.
MIT