summaryrefslogtreecommitdiff
path: root/reference/CPLUSPLUS/SYNTAX/class.html
diff options
context:
space:
mode:
authorTobias Klauser <tklauser@distanz.ch>2008-01-27 11:37:44 +0100
committerTobias Klauser <tklauser@xenon.tklauser.home>2008-01-27 11:37:44 +0100
commit7e0f021a9aec35fd8e6725e87e3313b101d26f5e (patch)
treeb1cacc4b24393f517aeb4610e9e1021f954307a8 /reference/CPLUSPLUS/SYNTAX/class.html
Initial import (2.0.2-6)2.0.2-6
Diffstat (limited to 'reference/CPLUSPLUS/SYNTAX/class.html')
-rw-r--r--reference/CPLUSPLUS/SYNTAX/class.html185
1 files changed, 185 insertions, 0 deletions
diff --git a/reference/CPLUSPLUS/SYNTAX/class.html b/reference/CPLUSPLUS/SYNTAX/class.html
new file mode 100644
index 0000000..45ec2af
--- /dev/null
+++ b/reference/CPLUSPLUS/SYNTAX/class.html
@@ -0,0 +1,185 @@
+<title>CLASS keyword</title>
+<!-- Changed by: Martin Leslie, 14-Mar-1996 -->
+<body bgcolor=#dddddd>
+<font color=brown>
+<hr>
+<center><h1>class keyword</h1></center>
+<hr>
+<p>
+The concept of a class
+allows you to
+<a href=../../C/glossary.html#encapsulation>encapsulate</a>
+ a set of related variables and only
+allow access to them via predetermined functions.
+<p>
+
+The <b>class</b> keyword is used to declare the group of variables
+and functions and the visability of the variables and functions.
+Here is a basic example.
+
+<p>
+<center>
+<table width="80%" border="1" bgcolor="ivory">
+<tr>
+<td>
+<pre>
+
+ class String
+ {
+ public:
+
+ void Set(char *InputStr) // Declare an Access function
+ {
+ strcpy(Str, InputStr);
+ }
+
+ private:
+
+ char Str[80]; // Declare a hidden variable.
+
+ };
+</pre>
+</td>
+</tr>
+</table>
+</center>
+<p>
+
+<ul>
+<li><b>private:</b> means that all variables and functions that
+ follow are only visable from within the class.
+
+<li><b>public:</b> all functions and variables that follow this
+ statement can be accessed from outside the class.
+</ul>
+
+Now we have declared a class called <b>String</b> we need to
+use it.
+<p>
+<center>
+<table width="80%" border="1" bgcolor="ivory">
+<tr>
+<td>
+<pre>
+
+ main()
+ {
+ String Title;
+
+ Title.Set("My First Masterpiece.");
+ }
+</pre>
+</td>
+</tr>
+</table>
+</center>
+<p>
+
+This code creates a String
+<a href=../../C/glossary.html#class_object>object</a>
+called Title and then uses the <b>Set</b> member function
+to initialise the value of <b>Str</b>.
+<p>
+In C++ the member function <b>Set</b> is also known as a
+<a href=../../C/glossary.html#method>method</a>
+<p>
+This is the strength
+of object oriented programming, the ONLY way to change
+<b>Str</b> is via the <b>Set</b> method.
+
+<p>
+
+The final code example brings the last two examples together
+ands a new method (called Get) that shows the contents of
+<b>Str</b>
+
+<p>
+<center>
+<table width="80%" border="1" bgcolor="ivory">
+<tr>
+<td>
+<pre>
+
+ #include &lt;stdlib.h&gt;
+ #include &lt;iostream.h&gt; // Instead of stdio.h
+
+ class String
+ {
+ public:
+
+ void Set(char *InputStr) // Declare an Access function
+ {
+ strcpy(Str, InputStr);
+ }
+ <b>
+ char *Get(void) // Declare an Access function
+ {
+ return(Str);
+ }
+ </b>
+
+ private:
+
+ char Str[80]; // Declare a hidden variable.
+
+ };
+
+ main()
+ {
+ String Title;
+
+ Title.Set("My First Masterpiece.");
+
+ <b>cout << Title.Get() << endl;</b>
+ }
+</pre>
+</td>
+</tr>
+</table>
+</center>
+<p>
+
+
+<hr>
+<h2>Examples:</h2>
+<img src="../../GRAPHICS/computer.gif">
+<a href="../EXAMPLES/class1.cc">Example program.</a>
+<hr>
+<h2>See Also:</h2>
+
+<img src="../../GRAPHICS/whiteball.gif">
+<a href="../CONCEPT/constructor.html">Constructors and destructors.</a>
+<p>
+<img src="../../GRAPHICS/whiteball.gif">
+<a href="../CONCEPT/inheritance.html">Class Inheritance.</a>
+<hr>
+
+</font>
+<font color=black>
+<h2>C References</h2>
+<p>
+
+<hr>
+<p>
+<center>
+<table border=2 width=80% bgcolor="ivory">
+<tr align=center>
+<td width="25%">
+<a href="../cref.html">Top</a>
+</td><td width="25%">
+<a href="../../C/master_index.html">Master Index</a>
+</td><td width="25%">
+<a href="keywords.html">C++ Keywords</a>
+</td><td width="25%">
+<a href="../../C/FUNCTIONS/funcref.htm">Functions</a>
+</td>
+</tr>
+</table>
+</center>
+<p>
+<hr>
+<font color=brown>
+<address>Martin Leslie
+08-Feb-96</address><p>
+</font>
+