Desktop_TelephoneTools/Database/MysqlDataParam.vb

Imports System.Text

Public Class MysqlDataParam
    Enum DataTypeEnum
        '###############################数值类型#############################
        ''' <summary>
        ''' 1 byte,小整数值
        ''' </summary>
        Tinyint

        ''' <summary>
        ''' 2 bytes,大整数值
        ''' </summary>
        Smallint

        ''' <summary>
        ''' 3 bytes,大整数值
        ''' </summary>
        Mediumint

        ''' <summary>
        ''' 4 bytes,大整数值
        ''' </summary>
        Int

        ''' <summary>
        ''' 4 bytes,大整数值
        ''' </summary>
        [Integer]

        ''' <summary>
        ''' 8 bytes,极大整数值
        ''' </summary>
        Bigint

        ''' <summary>
        ''' 4 bytes,单精度浮点数值
        ''' </summary>
        Float


        ''' <summary>
        ''' 8 bytes,双精度浮点数值
        ''' </summary>
        [Double]



        '####################日期类型###############################

        ''' <summary>
        ''' 对DECIMAL(M,D) ，如果M>D，为M+2否则为D+2.小数值
        ''' </summary>
        [Decimal]

        ''' <summary>
        ''' 3 bytes,日期值,YYYY-MM-DD
        ''' </summary>
        [Date]


        ''' <summary>
        ''' 3 bytes,时间值或持续时间,HH:MM:SS
        ''' </summary>
        Time


        ''' <summary>
        ''' 1 bytes,年份值,YYYY
        ''' </summary>
        Year


        ''' <summary>
        ''' 8 bytes,混合日期和时间值,YYYY-MM-DD HH:MM:SS
        ''' </summary>
        Datetime

        ''' <summary>
        ''' 4 bytes,混合日期和时间值，时间戳,YYYYMMDD HHMMSS
        ''' </summary>
        Timestamp


        '####################字符类型###############################

        ''' <summary>
        ''' 0-255 bytes,定长字符串
        ''' </summary>
        [Char]

        ''' <summary>
        ''' 0-65535 bytes,变长字符串
        ''' </summary>
        Varchar

        ''' <summary>
        ''' 0-255 bytes,不超过 255 个字符的二进制字符串
        ''' </summary>
        Tinyblob


        ''' <summary>
        ''' 0-255 bytes,短文本字符串
        ''' </summary>
        Tinytext

        ''' <summary>
        ''' 0-65 535 bytes,二进制形式的长文本数据
        ''' </summary>
        Blob

        ''' <summary>
        ''' 0-65 535 bytes,长文本数据
        ''' </summary>
        Text


        ''' <summary>
        ''' 0-16 777 215 bytes,二进制形式的中等长度文本数据
        ''' </summary>
        Mediumblob

        ''' <summary>
        ''' 	0-16 777 215 bytes,中等长度文本数据
        ''' </summary>
        Mediumtext

        ''' <summary>
        ''' 0-4 294 967 295 bytes,二进制形式的极大文本数据
        ''' </summary>
        Longblob

        ''' <summary>
        ''' 0-4 294 967 295 bytes,极大文本数据
        ''' </summary>
        Longtext
    End Enum

    ''' <summary>
    ''' 列名
    ''' </summary>
    ''' <returns></returns>
    Public Property ColumnName() As String

    ''' <summary>
    ''' 当前值
    ''' </summary>
    ''' <returns></returns>
    Public Property Value() As String


    ''' <summary>
    ''' 默认值
    ''' </summary>
    ''' <returns></returns>
    Public Property DefaultValue() As String

    ''' <summary>
    ''' 数据类型
    ''' </summary>
    ''' <returns></returns>
    Public Property DataType() As DataTypeEnum

    ''' <summary>
    ''' 数据类型长度
    ''' </summary>
    ''' <returns></returns>
    Public Property DataTypeLength() As Integer

    ''' <summary>
    ''' 数据类型是否带符号
    ''' </summary>
    ''' <returns></returns>
    Public Property IsUnsigned() As Boolean



    ''' <summary>
    ''' 是否允许为空
    ''' </summary>
    ''' <returns></returns>
    Public Property IsNull() As Boolean = True

    ''' <summary>
    ''' 是否自动增长
    ''' </summary>
    ''' <returns></returns>
    Public Property IsAutoIncrement() As Boolean

    ''' <summary>
    ''' 是否为主键
    ''' </summary>
    ''' <returns></returns>
    Public Property IsPrimaryKey() As Boolean

    Public Function ToAddColString() As String
        Dim sb As New StringBuilder
        sb.Append($"`{ColumnName}`")

        Select Case DataType
            Case DataTypeEnum.Varchar, DataTypeEnum.[Char]
                sb.Append($" {DataType}({DataTypeLength}) ")
            Case DataTypeEnum.Int
                sb.Append($" {DataType}")
                If IsUnsigned Then sb.Append($" Unsigned")
                If IsAutoIncrement Then sb.Append($" AUTO_INCREMENT")
            Case Else
                sb.Append($" {DataType}")
        End Select

        sb.Append(IIf(IsNull, " Default Null", " Not Null"))

        If IsPrimaryKey Then
            sb.Append($" PRIMARY KEY")
        End If

        Return sb.ToString()
    End Function
End Class