VB.NET語法part1_初階_變數宣告_函數使用_字串用法

File --> New Project --> Visual Basic --> Console Application


VB變數宣告法

Dim 變數名 As 資料型態

Dim 變數名 As 資料型態 = 變數數值


VB常數(Constant)

Const 變數名 As 資料型態

Const 變數名 As 資料型態 = 變數數值

VB之基本一般輸出

有自動換行
Console.WriteLine()


無自動換行
Console.Write()


VB之特定格式之輸出

Console.WriteLine("..{0}...{1}....{2}.." , 變數1,變數2,變數3)

Module Module1

    Sub Main()
        '一般變數宣告'
        Dim idNo As String
        Dim yrRate As Double
        Dim year As Integer
        '一般變數宣告後之賦值'
        Dim idNo2 As String = "1234"
        Dim year2 As Integer = 28


        '常數變數宣告'
        Const PI As Double = 3.14
        Const stuName As String = "Sam"
        Const eulerNum As Double = 2.718

        '輸出'
        Console.Write("無換行書出")
        Console.WriteLine("有換行輸出")
        '特定對應參數之輸出'
        Dim strName As String = "Mark"
        Dim age As Integer = 24
        Console.WriteLine("{0}同學今年{1}歲!", strName, age)


        Console.ReadKey()
    End Sub

End Module

VB之基本一般輸入

Module Module1

    Sub Main()
        Dim usrName As String
        Console.Write("請輸入自己的姓名")
        usrName = Console.ReadLine()
        Console.WriteLine("{0}歡迎登入...", usrName)
        Console.WriteLine("按一下Enter結束")
        Console.Read()
    End Sub

End Module

VB之自訂函數

[修飾詞] Function 函數名稱([引數串列]) As 回傳值型態
    [敘述區段]
    Return 運算式   or  函數名稱 = 運算式
    [Exit Function]
    [敘述區段]
End Function











請設計一個計算圓面積之函數