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[VB.NET]老问题,插入数据并发错误?

2008-12-25 21:56 190 查看
老问题,插入数据并发错误?
''简单的数据存取.动态表.有主键,原因在于未能自动提升主键值。(用自动生成的数据集就没此问题)
Imports System.Data.SqlClient
Public Class Form1

Dim comm As New SqlClient.SqlConnection
Dim ad As New SqlDataAdapter("SELECT * FROM 数据表", comm)

Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load

Dim st As String = "D:/temp/sql.mdf"
Dim SqTex As String = "Data Source=./SQLEXPRESS;AttachDbFilename=" & st & ";Integrated Security=True;Connect Timeout=30;User Instance=True"
comm.ConnectionString = SqTex
comm.Open()

Dim dber As New SqlCommandBuilder(ad)
ad.DeleteCommand = dber.GetDeleteCommand
ad.InsertCommand = dber.GetInsertCommand
ad.UpdateCommand = dber.GetUpdateCommand

Dim ds As New DataSet
ad.FillSchema(ds, SchemaType.Mapped, "数据表")
ad.Fill(ds, "数据表")

DataGridView1.DataSource = ds
DataGridView1.DataMember = "数据表"

End Sub

Private Sub DataGridView1_CellEndEdit(ByVal sender As Object, ByVal e As System.Windows.Forms.DataGridViewCellEventArgs) Handles DataGridView1.CellEndEdit
Try
Me.Validate()
Catch
End Try
Dim ds As DataSet =Ctype(DataGridView1.DataSource ,DataSet)
ad.Update(ds, "数据表")
End Sub

End Class
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什么问题?
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用解除约束试一试。
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引用 1 楼 qinhl99 的回复:
什么问题?

1.)创建一个测试表
如:
(先写入一条或多条记录)
AAA BBB HHH 序号 ''----序号设为主键
.. .. .. 0
贴上代码执行,插入一条记录看会发生什么?
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今天忠于将问题解决了。还是老方法。
Dim cn As New SqlCommand("SELECT MAX(序号) FROM 数据表", comm)
Dim sd As Integer = cn.ExecuteScalar + 1

ds.Tables("数据表").Columns("序号").AutoIncrement = True
ds.Tables("数据表").Columns("序号").AutoIncrementSeed = sd
ds.Tables("数据表").Columns("序号").AutoIncrementStep = 1
''----------------------------
用SQL语句设置的主键在更新的时候都要刷新填充表,表会滚动,
不知还有更好的方法?
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来学习了.
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