c#&vb两种语言语法的简要介绍

c#&vb两种语言语法的简要介绍

1.变量声名
C# 语法
int x;
String s;
String s1, s2;
Object o;
Object obj = new Object();
public String name;
VB语法
Dim x As Integer
Dim s As String
Dim s1, s2 As String
Dim o 'Implicitly Object
Dim obj As New Object()
Public name As String

2语句
C#:
Response.Write("中文c#技术站");
VB:
Response.Write("中文c#技术站")

3.注释语句
//中文c#技术站
/*
欢迎访问
，
中文c#技术站
*/

VB:
'中文c#技术站

4.获得URL 传递的变量
C#:
String s = Request.QueryString["Name"];
String value = Request.Cookies["key"];
VB:
Dim s, value As String
s = Request.QueryString("Name")
value = Request.Cookies("Key").Value
5.声明属性
C#:
public String name {

get {
...
return ...;
}

set {
... = value;
}

}

VB:
Public Property Name As String

Get
...
Return ...;
End Get

Set
... = Value;
End Set

End Property
6.数组
C#
String[] a = new String[3];
a[0] = "1";
a[1] = "2";
a[2] = "3";
//二维数组
String[][] a = new String[3][3];
a[0][0] = "1";
a[1][0] = "2";
a[2][0] = "3";
VB:
Dim a(3) As String
a(0) = "1"
a(1) = "2"
a(2) = "3"

Dim a(3,3) As String
a(0,0) = "1"
a(1,0) = "2"
a(2,0) = "3"

Dim a() As String
a(0,0) = "1"
a(1,0) = "2"
a(2,0) = "3"

Dim a(,) As String
a(0,0) = "1"
a(1,0) = "2"
a(2,0) = "3"

7变量初始化
C#:
String s = "Hello World";
int i = 1
double[] a = { 3.00, 4.00, 5.00 };
VB:
Dim s As String = "Hello World"
Dim i As Integer = 1
Dim a() As Double = { 3.00, 4.00, 5.00 }

8;判断语句(If 语句)
if (Request.QueryString != null) {
...
}

VB:
If Not (Request.QueryString = Null)
...
End If

9.分支语句(case 语句)
C#:
switch (FirstName) {
case "John" :
...
break;
case "Paul" :
...
break;
case "Ringo" :
...
break;
}
VB:
Select (FirstName)
case "John" :
...
case "Paul" :
...
case "Ringo" :
...
End Select

10 For循环语句
C#
for (int i=0; i<3; i++)
a(i) = "test";
VB:
Dim I As Integer
For I = 0 To 2
a(I) = "test"
Next

11 While 循环
C#:
int i = 0;
while (i<3) {
Console.WriteLine(i.ToString());
i += 1;
}
VB:
Dim I As Integer
I = 0
Do While I < 3
Console.WriteLine(I.ToString())
I = I + 1
Loop
12 字符串连接
C#:
String s1;
String s2 = "hello";
s2 += " world";
s1 = s2 + " !!!";
VB:
Dim s1, s2 As String
s2 = "hello"
s2 &= " world"
s1 = s2 & " !!!"

声明事件
C#:
void MyButton_Click(Object sender,
EventArgs E) {
...
}
VB:
Sub MyButton_Click(Sender As Object,
E As EventArgs)
...
End Sub

13 声明Object
C#
MyObject obj = (MyObject)Session["Some Value"];
IMyObject iObj = obj
VB:
Dim bj As MyObject
Dim iObj As IMyObject
obj = Session("Some Value")
iObj = CType(obj, IMyObject)

14 数据类型转换
C#
int i = 3;
String s = i.ToString();
double d = Double.Parse(s);
VB:
Dim i As Integer
Dim s As String
Dim d As Double

i = 3
s = i.ToString()
d = CDbl(s)

15 类的声明和继承
C#:
using System;

namespace MySpace {

public class Foo : Bar {

int x;

public Foo() { x = 4; }
public void Add(int x) { this.x += x; }
public int GetNum() { return x; }
}

}

VB:
Imports System

Namespace MySpace

Public Class Foo : Inherits Bar

Dim x As Integer

Public Sub New()
MyBase.New()
x = 4
End Sub

Public Sub Add(x As Integer)
Me.x = Me.x + x
End Sub

Public Function GetNum() As Integer
Return x
End Function

End Class

End Namespace

16 声明类的主函数
C#:
using System;

public class ConsoleCS {

public ConsoleCS() {
Console.WriteLine("Object Created");
}

public static void Main (String[] args) {
Console.WriteLine("Hello World");
ConsoleCS ccs = new ConsoleCS();
}

}

VB
Imports System

Public Class ConsoleVB

Public Sub New()
MyBase.New()
Console.WriteLine("Object Created")
End Sub

Public Shared Sub Main()
Console.WriteLine("Hello World")
Dim cvb As ConsoleVB
cvb = New ConsoleVB()
End Sub

End Class

17 标准模块
C#
using System;

public class Module {

public static void Main (String[] args) {
Console.WriteLine("Hello World");
}

}
VB:
Imports System

Public Module ConsoleVB

Public Sub Main()
Console.WriteLine("Hello World")
End Sub

End Module