Representation of a header value in the form:

value; parameter1=value1; parameter2=value2

HeaderValue can be used to conveniently build and parse header values on this form.

To build an accepts header with the value

text/plain; q=0.3, text/html

use code like this:

HttpClientRequest request = ...;
var v = new HeaderValue("text/plain", {"q": "0.3"});
request.headers.add(HttpHeaders.ACCEPT, v);
request.headers.add(HttpHeaders.ACCEPT, "text/html");

To parse the header values use the parse static method.

HttpRequest request = ...;
List<String> values = request.headers[HttpHeaders.ACCEPT];
values.forEach((value) {
  HeaderValue v = HeaderValue.parse(value);
  // Use v.value and v.parameters

An instance of HeaderValue is immutable.

Implemented by

Static Methods

parse(String value, { String parameterSeparator: ";", String valueSeparator: null, bool preserveBackslash: false }) HeaderValue

Creates a new header value object from parsing a header value string with both value and optional parameters.


HeaderValue([String value = "", Map<String, String> parameters ])

Creates a new header value object setting the value and parameters.



parameters Map<String, String>

Gets the map of parameters.

value String

Gets the header value.

hashCode int

The hash code for this object.

read-only, inherited
runtimeType Type

A representation of the runtime type of the object.

read-only, inherited


operator ==(other) bool

The equality operator.



toString() String

Returns the formatted string representation in the form:

noSuchMethod(Invocation invocation) → dynamic

Invoked when a non-existent method or property is accessed.