Complete set: Intro to C - Bill Buchanan

4 Types and Debugging
4.1 Introduction
This module covers the key elements of arrays, indexers and collections. It covers:
• Reference types.
• Common reference type.
• Namespaces and object hierarchy.
• Debugging.
4.2 Reference Types
Parameters are passed into function member, such as methods or properties,
either using a value or a reference. If a value is passed, only the contents of
the value are used, thus it cannot be modified. It a reference it passed, the
function member can modify the value. A value passed by reference uses the
ref keyword, such as:
swap(ref int a, ref int b)
duction to .NET
Intro
4.2.1 Passing Value-Type Parameters
This is the simplest case, where a copy of the value of the data is passed. Thus an
changes to the parameters will be lost. For example in Figure 4.1 the value of val1 is
passed in x. This is then modified in the method to give the square of the value.
When it returns from the method, it can be seen from the sample run that the value
of val1 has not change (as it remains at 10).
Program 4.1: Program4_1_PassingByValue
using System;
namespace ConsoleApplication2
{
class Class1
{
static double findSquare(double x)
{
Agilent .NET Course: Type and Debugging 2