quarks.sgml

GLib是GTK+和GNOME工程的基础底层核心程序库

<!-- ##### SECTION Title ##### -->
Quarks

<!-- ##### SECTION Short_Description ##### -->
a 2-way association between a string and a unique integer identifier.

<!-- ##### SECTION Long_Description ##### -->
<para>
Quarks are associations between strings and integer identifiers.
Given either the string or the #GQuark identifier it is possible to
retrieve the other.
</para>
<para>
Quarks are used for both
<link linkend="glib-datasets">Datasets</link> and
<link linkend="glib-keyed-data-lists">Keyed Data Lists</link>.
</para>
<para>
To create a new quark from a string, use g_quark_from_string() or
g_quark_from_static_string().
</para>
<para>
To find the string corresponding to a given #GQuark, use g_quark_to_string().
</para>
<para>
To find the #GQuark corresponding to a given string, use g_quark_try_string().
</para>

<!-- ##### SECTION See_Also ##### -->
<para>

</para>

<!-- ##### TYPEDEF GQuark ##### -->
<para>
A GQuark is an integer which uniquely identifies a particular string.
</para>


<!-- ##### FUNCTION g_quark_from_string ##### -->
<para>
Gets the #GQuark identifying the given string.
If the string does not currently have an associated #GQuark, a new
#GQuark is created, using a copy of the string.
</para>

@string: a string.
@Returns: the #GQuark identifying the string.


<!-- ##### FUNCTION g_quark_from_static_string ##### -->
<para>
Gets the #GQuark identifying the given (static) string.
If the string does not currently have an associated #GQuark, a new
#GQuark is created, linked to the given string.
</para>
<para>
Note that this function is identical to g_quark_from_string() except
that if a new #GQuark is created the string itself is used rather than
a copy. This saves memory, but can only be used if the string will
always exist (if, for example, it is a statically-allocated string).
</para>

@string: a string.
@Returns: the #GQuark identifying the string.


<!-- ##### FUNCTION g_quark_to_string ##### -->
<para>
Gets the string associated with the given #GQuark.
</para>

@quark: a #GQuark.
@Returns: the string associated with the #GQuark.


<!-- ##### FUNCTION g_quark_try_string ##### -->
<para>
Gets the #GQuark associated with the given string, or 0 if the string has
no associated #GQuark.
</para>
<para>
If you want the GQuark to be created if it doesn't already exist, use
g_quark_from_string() or g_quark_from_static_string().
</para>

@string: a string.
@Returns: the #GQuark associated with the string, or 0 if there is no
#GQuark associated with the string.