코드 예제를 통한 다양한 언어의 프로그래밍 개념 비교
다음은 키워드로 요약할 수 없는 기본 프로그래밍 개념에 대한 예제 코드입니다. 자세한 내용은 다양한 언어의 키워드 비교을 참조하십시오.
다음 작업에 대한 코드 예제를 찾아 볼 수 있습니다.
할당문
주석
조건문
변수 선언
For 루프
제네릭 형식
기본 클래스 멤버 숨기기
값 형식 초기화
참조로 전달하는 매개 변수
값으로 전달하는 매개 변수
선택문
개체 참조를 Nothing으로 설정
구조적 예외 처리
While 루프
변수 선언
Visual Basic
Dim x As Integer
Public x As Integer = 10
Dim x = 10
C++
int x;
int x = 10;
var x = 10;
C#
int x;
int x = 10;
/F
let x = 10
주석
Visual Basic
' comment
x = 1 ' comment
Rem comment
C++
// comment
/* multiline
comment */
C#
// comment
/* multiline
comment */
/F
// comment
(* multiline
comment *)
할당문
Visual Basic
nVal = 7
C++
nVal = 7;
C#
nVal = 7;
/F
nVal <- 7
조건문
Visual Basic
If nCnt <= nMax Then
nTotal += nCnt ' Same as nTotal = nTotal + nCnt.
nCnt += 1 ' Same as nCnt = nCnt + 1.
Else
nTotal += nCnt
nCnt -= 1
End If
C++
if(nCnt < nMax) {
nTotal += nCnt;
nCnt++;
}
else {
nTotal += nCnt;
nCnt --;
};
C#
if (nCnt <= nMax)
{
nTotal += nCnt;
nCnt++;
}
else
{
nTotal +=nCnt;
nCnt--;
}
/F
if (nCnt <= nMax) then
nTotal <- nTotal + nCnt
nCnt <- nCnt + 1
else
nTotal <- nTotal + nCnt
nCnt <- nCnt - 1
선택문
Visual Basic
Select Case n
Case 0
MsgBox ("Zero")
' Visual Basic exits the Select at the end of a Case.
Case 1
MsgBox ("One")
Case 2
MsgBox ("Two")
Case Else
MsgBox ("Default")
End Select
C++
switch(n) {
case 0:
printf_s("Zero\n");
break;
case 1:
printf_s("One\n");
break;
case 2:
printf_s("Two\n");
break;
default:
printf_s("?\n");}
C#
switch(n)
{
case 0:
Console.WriteLine("Zero");
break;
case 1:
Console.WriteLine("One");
break;
case 2:
Console.WriteLine("Two");
break;
default:
Console.WriteLine("?");
break;
}
/F
n을 찾습니다
| 0 -> Console.WriteLine("Zero")
| 1 -> Console.WriteLine("One")
| 2 -> Console.WriteLine("Two")
| _ -> Console.WriteLine("?")
For 루프
Visual Basic
For n = 1 To 10
MsgBox("The number is " & n)
Next
For Each prop In obj
prop = 42
Next prop
C++
for(int n=1; n<11; n++)
printf_s("%d\n",n);
C#
for (int i = 1; i <= 10; i++)
Console.WriteLine("The number is {0}", i);
foreach (int i in testArr)
{
Console.WriteLine(i);
}
/F
for i = 1 to 10 do
printfn "%d" i
for i in testCollection do
printfn "%d" i
기본 클래스 멤버 숨기기
Visual Basic
Public Class BaseCls
Public Z As Integer = 100 ' The element to be shadowed
public Sub Test()
System.Console.WriteLine("Test in BaseCls")
End Sub
End Class
Public Class DervCls
Inherits BaseCls
Public Shadows Z As String = "*" ' The shadowing element.
public Shadows Sub Test()
System.Console.WriteLine("Test in DervCls")
End Sub
End Class
Public Class UseClasses
Dim BObj As BaseCls = New DervCls() ' DervCls widens to BaseCls.
Dim DObj As DervCls = New DervCls() ' Access through derived class.
Public Sub ShowZ()
System.Console.WriteLine("Accessed through base class: " & BObj.Z)
System.Console.WriteLine("Accessed through derived class: " & DObj.Z)
BObj.Test()
DObj.Test()
End Sub
End Class
C++
#using <mscorlib.dll>
#include <stdio.h>
public __gc class BaseCls
{
public:
int Z; // The element to be hidden
void Test()
{
printf_s("Test in BaseCls\n");
}
};
public __gc class DervCls : public BaseCls
{
public:
char Z; // The hiding element
void Test()
{
printf_s("Test in DervCls\n");
}
};
public __gc class UseClasses
{
public:
BaseCls * BObj; // DervCls widens to BaseCls
DervCls * DObj; // Access through derived class
void ShowZ()
{
BObj = new DervCls;
BObj->Z = 100;
DObj = new DervCls;
DObj->Z = '*';
printf_s("Accessed through base class: %d\n", BObj->Z);
printf_s("Accessed through derived class: %c\n", DObj->Z);
BObj->Test();
DObj->Test();
}
};
C#
public class BaseCls
{
public int Z = 100; // The element to be hidden
public void Test()
{
System.Console.WriteLine("Test in BaseCls");
}
}
public class DervCls : BaseCls
{
public new string Z = "*"; // The hiding element
public new void Test()
{
System.Console.WriteLine("Test in DervCls");
}
}
public class UseClasses
{
BaseCls BObj = new DervCls(); // DervCls widens to BaseCls
DervCls DObj = new DervCls(); // Access through derived class
public void ShowZ()
{
System.Console.WriteLine("Accessed through base class: {0}", BObj.Z);
System.Console.WriteLine("Accessed through derived class: {0}", DObj.Z);
BObj.Test();
DObj.Test();
}
}
/F
type BaseCls() =
member this.Z = 100
member this.Test() =
System.Console.WriteLine("Test in BaseCls")
type DervCls() =
inherit BaseCls()
member this.Z = "*"
member this.Test() =
System.Console.WriteLine("Test in DervCls")
type UseClasses() =
let BObj : BaseCls = new DervCls() :> BaseCls
let DObj : DervCls = new DervCls()
member this.ShowZ() =
System.Console.WriteLine("Accessed through base class: {0}", BObj.Z)
System.Console.WriteLine("Accessed through derived class: {0}", DObj.Z)
BObj.Test()
DObj.Test()
let useClassesObj = new UseClasses()
useClassesObj.ShowZ()
While 루프
Visual Basic
While n < 100 ' Test at start of loop.
n += 1 ' Same as n = n + 1.
End While '
C++
while(int n < 100)
n++;
C#
while (n < 100)
n++;
/F
while n < 100 do
n <- n + 1
값으로 전달하는 매개 변수
Visual Basic
Public Sub ABC(ByVal y As Long) ' The argument Y is passed by value.
' If ABC changes y, the changes do not affect x.
End Sub
ABC(x) ' Call the procedure.
' You can force parameters to be passed by value, regardless of how
' they are declared, by enclosing the parameters in extra parentheses.
ABC((x))
C++
testMethod(i,j);
C#
/* Note that there is no way to pass reference types (objects) strictly by value.
You can choose to either pass the reference (essentially a pointer),
or a reference to the reference (a pointer to a pointer).*/
// The method:
void ABC(int x)
{
...
}
// Calling the method:
ABC(i);
/F
let ABC(x) =
...
ABC(i)
참조로 전달하는 매개 변수
Visual Basic
Public Sub ABC(ByRef y As Long)
' The parameter y is declared by by referece:
' If ABC changes y, the changes are made to the value of x.
End Sub
ABC(x) ' Call the procedure.
C++
// Prototype of ABC that takes a pointer to integer.
int ABC(long *py);
ABC(&VAR);
// Prototype of ABC that takes a reference to integer.
int ABC(long &y);
ABC(VAR);
C#
/* Note that there is no way to pass reference types (objects) strictly by value.
You can choose to either pass the reference (essentially a pointer),
or a reference to the reference (a pointer to a pointer).*/
/* Note also that unsafe C# methods can take pointers just like C++ methods.
For details, see <MSHelp:link keywords="vclrfUnsafe" TABINDEX="0">unsafe</MSHelp:link>. */
// The method:
void ABC(ref int x)
{
...
}
// Calling the method:
ABC(ref i);
/F
let ABC(x : int byref) =
...
ABC(&i)
구조적 예외 처리
Visual Basic
Try
If x = 0 Then
Throw New Exception("x equals zero")
Else
Throw New Exception("x does not equal zero")
End If
Catch err As System.Exception
MsgBox("Error: " & Err.Description)
Finally
MsgBox("Executing finally block.")
End Try
C++
__try{
if (x == 0)
throw new Exception ("x equals zero");
else
throw new Exception ("x does not equal zero");
}
__catch(Exception e)
{
Console.WriteLine("Caught Exception");
}
__finally
{
Console.WriteLine("Executing finally block");
}
C#
// try-catch-finally
try
{
if (x == 0)
throw new System.Exception ("x equals zero");
else
throw new System.Exception ("x does not equal zero");
}
catch (System.Exception err)
{
System.Console.WriteLine(err.Message);
}
finally
{
System.Console.WriteLine("executing finally block");
}
/F
try
try
if x = 0 then
failwith "x equals zero"
else
failwith "x does not equal zero"
with
| Failure(msg) -> System.Console.WriteLine(msg)
finally
printfn "executing finally block"
개체 참조를 Nothing으로 설정
Visual Basic
o = Nothing
C++
o = nullptr; // when compiling with /clr
C#
o = null;
/F
// for an option type
o <- None
// when you really want a null value
o <- null
값 형식 초기화
Visual Basic
Dim dt as New System.DateTime(2001, 4, 12, 22, 16, 49, 844)
C++
System::DateTime dt = System::DateTime(2001, 4, 12, 22, 16, 49, 844);
C#
System.DateTime dt = new System.DateTime(2001, 4, 12, 22, 16, 49, 844);
/F
let dt = new System.DateTime(2001, 4, 12, 22, 16, 49, 844)
제네릭 형식
Visual Basic
' Define a generic type
Public Class classMaker(Of t)
' Constrain a type parameter
Public Class classMaker(Of t As IComparable)
' Create an object from a generic type
Dim integerClass As New classMaker(Of Integer)
C++
// Define a generic type
generic <typename T> ref class testList { ... };
// Constrain a type parameter
generic <typename T> where T : IComparable<T>
ref class testList { ... };
// Create an object from a generic type
testList<int>^ list = gcnew testList<int>();
C#
// Define a generic type
public class testList<T>{...}
// Constrain a type parameter
public class testList<T> where T : IComparable<T>
// Create an object from a generic type
testList<int> list = new testList<int>();
/F
// Define a generic type
type testList<'T> =
...
// Constraint a type parameter
type testList<'T when 'T :> IComparable<'T>>
// Create an object from a generic type
let list1 = new testList<int>()
참고 항목
참조
여러 언어 및 라이브러리에서 사용되는 컨트롤 및 프로그래밍 가능한 개체 비교