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HttpResponse class

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!');
  request.response.close();
});

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 = ...
response.headers.contentType
    = 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

IOSink

Constructors

HttpResponse()

Properties

bufferOutput ↔ bool read / write: Gets or sets if the HttpResponse should buffer output.
connectionInfo → HttpConnectionInfo? read-only: Gets information about the client connection. Returns null if the socket is not available.
contentLength ↔ int read / write: 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.
cookies → List<Cookie> read-only: Cookies to set in the client (in the 'set-cookie' header).
deadline ↔ Duration? read / write: 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.
done → Future read-only, inherited: A future that will complete when the consumer closes, or when an error occurs.
encoding ↔ Encoding read / write, inherited: The Encoding used when writing strings.
hashCode → int read-only, inherited: The hash code for this object.
headers → HttpHeaders read-only: Returns the response headers.
persistentConnection ↔ bool read / write: Gets and sets the persistent connection state. The initial value of this property is the persistent connection state from the request.
reasonPhrase ↔ String read / write: The reason phrase for the response.
runtimeType → Type read-only, inherited: A representation of the runtime type of the object.
statusCode ↔ int read / write: The status code of the response.

Methods

add(List<int> data) → void inherited: Adds byte data to the target consumer, ignoring encoding.
addError(Object error, [StackTrace? stackTrace]) → void inherited: Passes the error to the target consumer as an error event.
addStream(Stream<List<int>> stream) → Future inherited: Adds all elements of the given stream.
close() → Future inherited: 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 inherited: Returns a Future that completes once all buffered data is accepted by the underlying StreamConsumer.
noSuchMethod(Invocation invocation) → dynamic inherited: 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 inherited: A string representation of this object.
write(Object? object) → void inherited: 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 inherited: Iterates over the given objects and writes them in sequence.
writeCharCode(int charCode) → void inherited: Writes the character of charCode.
writeln([Object? object = ""]) → void inherited: Converts object to a String by invoking Object.toString and writes the result to this, followed by a newline.

Operators

operator ==(Object other) → bool inherited: The equality operator.

© 2012 the Dart project authors
Licensed under the BSD 3-Clause "New" or "Revised" License.
https://api.dart.dev/stable/2.18.5/dart-io/HttpResponse-class.html