HttpResponse class Null safety

An HTTP response, which returns the headers and data from the server to the client in response to an HTTP request.

Every HttpRequest object provides access to the associated HttpResponse object through the response property. The server sends its response to the client by writing to the HttpResponse object.

Writing the response

This class implements IOSink. After the header has been set up, the methods from IOSink, such as writeln(), can be used to write the body of the HTTP response. Use the close() method to close the response and send it to the client.

server.listen((HttpRequest request) {
  request.response.write('Hello, world!');

When one of the IOSink methods is used for the first time, the request header is sent. Calling any methods that change the header after it is sent throws an exception.

Setting the headers

The HttpResponse object has a number of properties for setting up the HTTP headers of the response. When writing string data through the IOSink, the encoding used is determined from the "charset" parameter of the "Content-Type" header.

HttpResponse response = ...
    = ContentType("application", "json", charset: "utf-8");
response.write(...);  // Strings written will be UTF-8 encoded.

If no charset is provided the default of ISO-8859-1 (Latin 1) will be used.

HttpResponse response = ...
response.headers.add(HttpHeaders.contentTypeHeader, "text/plain");
response.write(...);  // Strings written will be ISO-8859-1 encoded.

An exception is thrown if you use the write() method while an unsupported content-type is set.

Implemented types




bufferOutput bool
Gets or sets if the HttpResponse should buffer output.
read / write
connectionInfo HttpConnectionInfo?
Gets information about the client connection. Returns null if the socket is not available.
contentLength int
Gets and sets the content length of the response. If the size of the response is not known in advance set the content length to -1, which is also the default if not set.
read / write
cookies List<Cookie>
Cookies to set in the client (in the 'set-cookie' header).
deadline Duration?
Set and get the deadline for the response. The deadline is timed from the time it's set. Setting a new deadline will override any previous deadline. When a deadline is exceeded, the response will be closed and any further data ignored.
read / write
done Future
A future that will complete when the consumer closes, or when an error occurs.
encoding Encoding
The Encoding used when writing strings.
read / writeinherited
hashCode int
The hash code for this object.
headers HttpHeaders
Returns the response headers.
persistentConnection bool
Gets and sets the persistent connection state. The initial value of this property is the persistent connection state from the request.
read / write
reasonPhrase String
The reason phrase for the response.
read / write
runtimeType Type
A representation of the runtime type of the object.
statusCode int
The status code of the response.
read / write


add(List<int> data) → void
Adds byte data to the target consumer, ignoring encoding.
addError(Object error, [StackTrace? stackTrace]) → void
Passes the error to the target consumer as an error event.
addStream(Stream<List<int>> stream) Future
Adds all elements of the given stream.
close() Future
Close the target consumer.
detachSocket({bool writeHeaders = true}) Future<Socket>
Detaches the underlying socket from the HTTP server. When the socket is detached the HTTP server will no longer perform any operations on it.
flush() Future
Returns a Future that completes once all buffered data is accepted by the underlying StreamConsumer.
noSuchMethod(Invocation invocation) → dynamic
Invoked when a non-existent method or property is accessed.
redirect(Uri location, {int status = HttpStatus.movedTemporarily}) Future
Respond with a redirect to location.
toString() String
A string representation of this object.
write(Object? object) → void
Converts object to a String by invoking Object.toString and adds the encoding of the result to the target consumer.
writeAll(Iterable objects, [String separator = ""]) → void
Iterates over the given objects and writes them in sequence.
writeCharCode(int charCode) → void
Writes the character of charCode.
writeln([Object? object = ""]) → void
Converts object to a String by invoking Object.toString and writes the result to this, followed by a newline.


operator ==(Object other) bool
The equality operator.