id生成器代码问题 [英] id generator code problem

问题描述

你做编码器..我面临着我的id号码生成器代码的问题

i我正在构建数据库项目，我想让id自动生成它我自己做了但不是我想要的它工作...我希望它从001开始增加每次+1喜欢这个002,003直到它达到100等等

它现在如何工作就像这从1开始然后2 ，3,4,5,6 ......这是代码。

谢谢。

hw u doing coders .. am facing problem with my code of id number generator
i am building database project and i want to make the id generates it self automaticaly i did it but not how i want it to work ...i want it to Start from 001 and increases every time +1 like this 002,003 untill it reach 100 and so on
how it works now is like this starts from 1 and then 2,3,4,5,6......here is the code.
thank you.

Sub GenerateSerialNo()
        Dim odr As SqlDataReader
        Dim sql As String
        sql = "select max(bookid)as SNo from tbremovedbooks"
        Try
            conn.Open()
            'Application.DoEvents()
            cmd = New SqlCommand(sql, conn)
            odr = cmd.ExecuteReader
            If odr.Read() Then
                iNumOfRecords = DS.Tables("tbremovedbooks").Rows.Count + 1
                'Displaying 1 if there is no data in the table
                If iNumOfRecords = 1 Then
                    txtbookid.Text = "1"
                Else
                    'Ordering the data Serial if more than one record is in the table
                    txtbookid.Text = odr("SNo") + 1
                End If
            End If
            odr.Close()
            cmd.Connection.Close()
            conn.Close()
        Catch ex As Exception
            MsgBox(ex.Message)
        End Try
    End Sub

推荐答案

为什么你不能把你的ID保存为整数，只需更改格式当你显示它时的数字？



基本上你没有什么可以赢得varchar主键。



因此，在数据库中，主键为int（1,2,3,4，...）。



当你想显示ID时：

Why on hell don''t you keep your ID as integer, and just change the format of the number when you are displaying it ?

Basically you have nothing to win to have a varchar primary key.

So, in the database, primary key as int (1, 2, 3, 4, ...).

When you want to display ID :

string formattedId = id.ToString("000");

简单有效。

Simple, and effective.

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