:relfileprefix: ../../
[#boost-urls-params_base]

= xref:boost.adoc[pass:[boost]]::xref:boost/urls.adoc[pass:[urls]]::params_base


Common functionality for containers


== Synopsis

Declared in header `<https://www.github.com/boostorg/url/blob/develop/include/boost/url/params_base.hpp#L39[boost/url/params_base.hpp,window=blank_]>`

[source,cpp,subs="verbatim,macros,-callouts"]
----
class params_base;
----

==  Types
[cols=2,separator=¦]
|===
¦Name ¦Description
¦xref:boost/urls/params_base/const_iterator.adoc[`const_iterator`]  ¦

xref:boost/urls/params_base/iterator.adoc[iterator]

¦xref:boost/urls/params_base/const_reference.adoc[`const_reference`]  ¦

The reference type

¦xref:boost/urls/params_base/difference_type.adoc[`difference_type`]  ¦

A signed integer type used to represent differences.

¦xref:boost/urls/params_base/iterator.adoc[`iterator`]  ¦

¦xref:boost/urls/params_base/reference.adoc[`reference`]  ¦

The reference type

¦xref:boost/urls/params_base/size_type.adoc[`size_type`]  ¦

An unsigned integer type to represent sizes.

¦xref:boost/urls/params_base/value_type.adoc[`value_type`]  ¦

The value type

|===
==  Member Functions
[cols=2,separator=¦]
|===
¦Name ¦Description
¦xref:boost/urls/params_base/begin.adoc[`begin`]  ¦

Return an iterator to the beginning

¦xref:boost/urls/params_base/buffer.adoc[`buffer`]  ¦

Return the referenced character buffer.

¦xref:boost/urls/params_base/contains.adoc[`contains`]  ¦

Return true if a matching key exists

¦xref:boost/urls/params_base/count.adoc[`count`]  ¦

Return the number of matching keys

¦xref:boost/urls/params_base/empty.adoc[`empty`]  ¦

Return true if there are no params

¦xref:boost/urls/params_base/end.adoc[`end`]  ¦

Return an iterator to the end

¦xref:boost/urls/params_base/find.adoc[`find`]  ¦

Find a matching key

¦xref:boost/urls/params_base/find_last.adoc[`find_last`]  ¦

Find a matching key

¦xref:boost/urls/params_base/size.adoc[`size`]  ¦

Return the number of params

|===
==  Static Member Functions
[cols=2,separator=¦]
|===
¦Name ¦Description
¦xref:boost/urls/params_base/max_size.adoc[`max_size`]  ¦

Return the maximum number of characters possible

|===

== Description


This base class is used by the library
to provide common member functions for
containers. This cannot be instantiated
directly; Instead, use one of the
containers or functions:

=== Containers

* xref:boost/urls/params_ref.adoc[params_ref]

* xref:boost/urls/params_view.adoc[params_view]

* xref:boost/urls/params_encoded_ref.adoc[params_encoded_ref]

* xref:boost/urls/params_encoded_view.adoc[params_encoded_view]



