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vb.net數(shù)據(jù)的增加 vb添加數(shù)據(jù)到數(shù)據(jù)庫

vb.net 在datagridview中增加,修改,刪除數(shù)據(jù),如何使這種改變(就是前面所說的增,修,刪)真正的改變數(shù)據(jù)庫

首先你的數(shù)據(jù)源就寫錯了

按需定制網(wǎng)站可以根據(jù)自己的需求進行定制,成都網(wǎng)站設計、成都做網(wǎng)站構思過程中功能建設理應排到主要部位公司成都網(wǎng)站設計、成都做網(wǎng)站的運用實際效果公司網(wǎng)站制作網(wǎng)站建立與制做的實際意義

strconn = "Provider =Microsoft.Jet.OLEDB.4.0;Data Source =E:\AccessDataBase\test2000.mdb"

應為

strconn = "Provider =Microsoft.Jet.OLEDB.4.0;Data Source =E:\\AccessDataBase\\test2000.mdb"

絕對路徑是"\\",這個要記得。

代碼我就不幫你寫了,說下我的思路,對于數(shù)據(jù)庫的操作,你只能1步步來做,也就是在dataGridView里做了修改以后就直接在數(shù)據(jù)庫里修改,打個比方,你想在dataGridView里添加數(shù)據(jù)A再刪除數(shù)據(jù)B,步驟如下:

1.你在dataGridView里添加了數(shù)據(jù)A

2.打開數(shù)據(jù)庫

3.在相應表下添加A

4.關閉數(shù)據(jù)庫

5.在dataGridView里刪除數(shù)據(jù)B

6.打開數(shù)據(jù)庫

7.在相應表里刪除數(shù)據(jù)B

8.關閉數(shù)據(jù)庫

看起來方法比較復雜,但是數(shù)據(jù)庫的操作必須這樣做,而且,記得,打開數(shù)據(jù)庫并操作結束后先關閉數(shù)據(jù)庫再做其他的任務。

vb.net 一個數(shù)組怎么添加新數(shù)據(jù)

list1.additem j 意思就是把j添加至list1列表中,這是在一個for 循環(huán)中,循環(huán)了10次,添加了10次 j,即 list1 中 有10列分別為:1,3,6,10,15,21,28,36,45,55

下面又來了一個循環(huán), list1.removeitem 刪除列,刪除的是 list1.listcount - i ,list1.listcount 就是總列數(shù)為10,減去 i ,i 是1到4,即10-1,9-2,8-3,7-4 每減掉一次,list1.listcount 就少了一條記錄。

(注意,list1.listcount-1 是最后一條記錄)

減掉了第 9,7,5,3列

剩余為 1,3,6,15,28,45

結果為:3,15,28

'ListCount返回列表框中的項目總數(shù)

'ListCount-1是列表框中最后一個項目的索引號

'虧你提醒了,我寫錯了,上面修改了,第一個索引為0,最后一個為9.

'也就是,問題所問的第二列的索引為1,第四列的索引為3...

一對多關聯(lián)的數(shù)據(jù)庫在VB.NET中如何新增記錄

script type="text/javascript" src="" /script

script type="text/javascript" src="" /script

有兩個表order(orderid,ordername,totalprice), orderdetail(orderid,productid,productname,price) 已經(jīng)建立一對多

關聯(lián)(orderid). 用VB.NET建立一個窗體, 用于主表和明細表的數(shù)據(jù)錄入及更新.

在窗體上增加兩個sqldataadapter,分別選擇order和orderdetail表, 并生成數(shù)據(jù)集,在DATASET中建立關聯(lián)(orderid) 主表中:ORDERID,ORDERNAME 綁定在兩個TEXTBOX文本框中,用于接受用戶的輸入,totalprice接受明細表中price

的匯總值.

明細表綁定到一個DATAGRID控件, datasource:dsorder; datamember:order.orderorderdetail建立的關聯(lián)名稱

問題: 在主表中新增一個記錄,用戶錄入orderid和ordername后,進入明細表的錄入,用戶錄入productid, productname, price后,提示 “明細orderID列不允許空值,要更正該值嗎?” 是什么原因?

用于連接主表的明細orderID如果輸入跟主表一樣的orderID時提示“ForeignKeyconstraint 要求在交叉表中存在子鍵值。要更正該值嗎?”

只有錄入主表中的orderid和ordername后, 先更新主表數(shù)據(jù)源,才可以編輯更新明細表,這是為什么? 請問,有沒有其他更好的方法, 實現(xiàn)主表和明細表的新增記錄同時更新呢? 謝謝關照! 網(wǎng)友:方宇 回復:

附部分源代碼:

Public Class fmOrders

Inherits System.Windows.Forms.Form

Dim WithEvents dtOrderDetails As New DataTable()

Dim BmOrders As BindingManagerBase

Dim BmOrderDetails As BindingManagerBase

Dim OrderDetailsHasChange As Boolean

Dim orderid As DataColumn

dim ordername as datacolumn

Dim SubTotal As DataColumn Private Sub bnFirst_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles bnFirst.Click

BmOrders.Position = 0

End Sub

Private Sub bnPrior_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles bnPrior.Click

BmOrders.Position -= 1

End Sub

Private Sub bnNext_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles bnNext.Click

BmOrders.Position += 1

End Sub

Private Sub bnLast_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles bnLast.Click

BmOrders.Position = BmOrders.Count - 1

End Sub Private Sub bnAdd_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles bnAdd.Click

Try

BmOrders.EndCurrentEdit()

BmOrders.AddNew()

Catch err As System.SystemException

MessageBox.Show(err.ToString)

End Try

End Sub

Private Sub bnLoad_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles bnLoad.Click

FillData()

End Sub Private Sub bnUpdate_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles bnUpdate.Click

Dim dsTestOrdersChange As DataSet BmOrderDetails.EndCurrentEdit()

BmOrders.EndCurrentEdit()

If Not dsTestOrders.HasChanges(DataRowState.Deleted) Then

Try

daOrders.Update(dsTestOrders, "Orders")

daOrderDetails.Update(dsTestOrders, "OrderDetails")

dsTestOrders.AcceptChanges()

Catch err As System.SystemException

dsTestOrders.RejectChanges()

MessageBox.Show(err.ToString)

Throw

End Try

Else

Try

daOrderDetails.Update(dsTestOrders, "OrderDetails")

daOrders.Update(dsTestOrders, "Orders")

dsTestOrders.AcceptChanges()

Catch err As System.SystemException

dsTestOrders.RejectChanges()

MessageBox.Show(err.ToString)

Throw

End Try

End If

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

FillData()

dtOrderDetails = dsTestOrders.Tables("OrderDetails")

BmOrders = Me.BindingContext(dsTestOrders, "Orders")

BmOrderDetails = Me.BindingContext(dsTestOrders, "Orders.OrdersOrderDetails")

OrderDetailsHasChange = True

SubTotal = dsTestOrders.Tables("Orders").Columns("SubTotal")

SubTotal.DefaultValue = 0

Price = dsTestOrders.Tables("OrderDetails").Columns("Price")

Price.DefaultValue = 0

End Sub Private Sub FillData()

dsTestOrders.EnforceConstraints = False

daOrders.Fill(dsTestOrders)

daOrderDetails.Fill(dsTestOrders)

dsTestOrders.EnforceConstraints = True

End Sub

Private Sub dtOrderDetails_ColumnChanged(ByVal sender As Object, ByVal e As System.Data.DataColumnChangeEventArgs) _

Handles dtOrderDetails.ColumnChanged Dim drOrders As DataRow

Dim drOrderDetails As DataRow

Dim iSubTotal As Integer

Try

If OrderDetailsHasChange Then

OrderDetailsHasChange = False

drOrders = dsTestOrders.Tables("Orders").Rows(BmOrders.Position)

iSubTotal = 0

For Each drOrderDetails In drOrders.GetChildRows("OrdersOrderDetails")

iSubTotal = iSubTotal + drOrderDetails("price")

Next

drOrders.BeginEdit()

drOrders("SubTotal") = iSubTotal

drOrders.EndEdit()

End If

Finally

OrderDetailsHasChange = True

End Try

End Sub Private Sub bndelete_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles bndelete.Click

If BmOrders.Count 0 Then

BmOrders.RemoveAt(BmOrders.Position)

End If

End Sub Private Sub bncancel_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles bncancel.Click

BmOrders.CancelCurrentEdit() End Sub

End Class script type="text/javascript" src="" /script

script type="text/javascript" src="" /script

vb.net實現(xiàn)數(shù)據(jù)庫的表增加一列?

一種是用ADO.NET來執(zhí)行alter table student add english int實現(xiàn)數(shù)據(jù)庫 表的列添加

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