La manipulación de datos (INSERT, UPDATE) usando conjunto de datos de objetos con VB.NET
https://stackoverflow.com/questions/1692402
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18-09-2019 - |
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Soy novato en el uso conjunto de datos. Estoy escribiendo un programa con VB.NET, no tengo que seleccionar datos de una tabla. Entonces tengo que actualizar aproximadamente 4 tablas e insertar a 2 tablas. ¿Qué enfoque estará bien para mí? Estoy pensando en usar conjunto de datos. Si alguien puede señalar que un problema, por favor, muéstrame con Código de ejemplo para actualizar conjunto de datos. que gracias a todos mucho.
Solución
Este es un enlace puede hacer referencia a:
Public Function CreateCommandAndUpdate( _
ByVal connectionString As String, _
ByVal queryString As String) As DataSet
Dim dataSet As DataSet = New DataSet
Using connection As New OleDbConnection(connectionString)
connection.Open()
Dim adapter As New OleDbDataAdapter()
adapter.SelectCommand = New OleDbCommand( _
queryString, connection)
Dim builder As OleDbCommandBuilder = _
New OleDbCommandBuilder(adapter)
adapter.Fill(dataSet)
' Code to modify the data in the DataSet here.
' Without the OleDbCommandBuilder this line would fail.
builder.GetUpdateCommand()
adapter.Update(dataSet)
End Using
Return dataSet
End Function
Y aquí está un ejemplo sobre cómo eliminar:
Private Sub btnDeleteUser_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnDeleteUser.Click
Dim reponse_del As Integer
If txtSearch.Text = "" Then
MessageBox.Show("Please type a user name into the text box")
End If
'clear and refill Dataset
OleDAPass.SelectCommand.Parameters("UserName").Value = txtSearch.Text
DS_Pass1.Clear()
OleDAPass.Fill(DS_Pass1)
'no records of the search name
If DS_Pass1.Tables("PwordStore").Rows.Count = 0 Then
MessageBox.Show("Record not found")
ElseIf DS_Pass1.Tables("PwordStore").Rows.Count = 1 Then 'record exists delete it
MessageBox.Show("Are you sure you wish to delete this user?", "Warning", MessageBoxButtons.YesNo, MessageBoxIcon.Exclamation)
If reponse_del = DialogResult.Yes Then
OleDAPass.SelectCommand.Parameters ("UserName").Value = txtSearch.Text
'delete row
DS_Pass1.Tables("PwordStore").Rows(0).Delete()
OleDAPass.Update(DS_Pass1, "PwordStore")
End If
DS_Pass1.PwordStore.AcceptChanges()
DS_Pass1.Clear()
txtSearch.Text = ""
End If
End Sub
Otros consejos
Debe trabajar con adaptador de datos - la mejor manera de aprender - buscar algunos ejemplos en MSDN o Google, entonces - intenta resolver su problema - entonces - si se encuentra con un problema - publicar aquí.
en lo básico: se necesita una conexión, un comando, un adaptador de datos y un conjunto de datos.
se utiliza datadapter relleno para obtener los datos de la base de datos para el conjunto de datos, y la actualización de los datos para poner de nuevo a la base de datos. Usted necesita decir el adaptador de datos cómo hacerlo, o utilizar un asistente para generar automáticamente los comandos (INSERT, UPDATE etc ...)
Public Function MaintanenceImport(ByVal con As IDbConnection, ByVal TransDate As Date, ByVal ds2 As DataSet)
Try
For index1 = 0 To ds2.Tables.Count - 1
tblname = ds2.Tables(index1).TableName
ds1 = Util.GetDataSet4Query(" select * from " & tblname & " ")
index = 0
ds1.Tables(index).TableName = "" & tblname & ""
'For index = 0 To ds1.Tables.Count - 1
str1 = ""
Str = ""
cnt1 = 0
' '====Comparing the Xml TableName and the Database Table Name
' '==== ds1-from Database;ds2-from xml
' If (ds1.Tables(index).TableName = ds2.Tables(index1).TableName) Then
' tblname = ds2.Tables(index1).TableName
l = 0
'=== Counting the Columns of xml dataset
While (l <= ds2.Tables(index1).Columns.Count - 1)
n = 0
'=== Counting the Columns of DataBase dataset
While (n <= ds1.Tables(index).Columns.Count - 1)
'==== Comparing the Column Names and seperating the matching and unmatching fields
If ((UCase(ds2.Tables(index1).Columns(l).ColumnName).Trim) = (UCase(ds1.Tables(index).Columns(n).ColumnName).Trim) = True) Then
f2 = True
Exit While
Else
f2 = False
End If
n += 1
End While
'=== Collecting the Unmatched Column Names
If f2 = False Then
cnt3 = cnt3 + 1
If cnt3 = 1 Then
str4 = ds2.Tables(index1).Columns(l).ColumnName
col1 = str4
m1 = 0
a1(m1) = 1
Else
str4 = str4 + "," + ds2.Tables(index1).Columns(l).ColumnName
m1 += 1
a1(m1) = l
End If
End If
'=== Collecting the matching column names
If f2 = True Then
cnt1 = cnt1 + 1
If cnt1 = 1 Then
str1 = ds2.Tables(index1).Columns(l).ColumnName
col = str1
m = 0
a(m) = l
Else
str1 = str1 + "," + ds2.Tables(index1).Columns(l).ColumnName
m += 1
a(m) = l
End If
End If
l += 1
End While
'=================================================================
'===> code to fetch value from xml for insert <====
'=================================================================
i = 0
'==== Take a row count of dataset from xml
While (i <= ds2.Tables(index1).Rows.Count - 1)
k = 0
f1 = False
'==== Take a row count of dataset from Database
While (k <= ds1.Tables(index).Rows.Count - 1)
'=== Comparing the First Field of the row
If (ds2.Tables(index1).Rows(i)(0).ToString() = ds1.Tables(index).Rows(k)(0).ToString()) Then
'== if matches true Else false
f1 = True
Exit While
Else
f1 = False
End If
k += 1
End While
'== if false it indicates NewRecord
If f1 = False Then
m = 0
'=================================================================
'===>if column names collected are similar to the dbase table<====
'=================================================================
If a Is Nothing Then
cnt = 0
cnt = cnt + 1
j = 0
While (j < ds2.Tables(index1).Columns.Count)
If cnt = 1 Then
Str = ds2.Tables(index1).Rows(i)(j).ToString()
q = str
Else
str = str + "," + "'" + Replace(ds2.Tables(index1).Rows(i)(j).ToString(), "'", "''") + "'"
cnt += 1
End If
j += 1
End While
'========================================================================
'===>if column names collected are not similar to the database table<====
'========================================================================
'=== Collecting the values
Else
m = 0
cnt = 0
cnt += 1
cnt2 = cnt1
For m = 0 To cnt2 - 1
p = a(m)
If p.ToString Is Nothing Then
Exit For
Else
If cnt = 1 Then
str = "'" + ds2.Tables(index1).Rows(i)(p).ToString() + "'"
'q = str
Else
str = str + "," + "'" + Replace(ds2.Tables(index1).Rows(i)(p).ToString(), "'", "''") + "'"
End If
cnt += 1
End If
Next
End If
Dim TransCon As IDbConnection
Dim Trans As IDbTransaction
Try
'== Inserting the collected values into table
TransCon = Util.GetConnection
TransCon.Open()
Trans = TransCon.BeginTransaction(IsolationLevel.ReadCommitted)
sql3 = "insert into " & tblname & "(" & str1 & ") values(" & str & ")"
'== Check Identity Column
If Util.ExecuteQryNSP(TransCon, CmdType.Text, ExecuteMode.ExecuteScalar, Trans, "select count(*) from SysColumns where Id=object_id('" & tblname & "') and Colstat&1=1") > 0 Then
Util.ExecuteQryNSP(TransCon, CmdType.Text, ExecuteMode.ExecuteNonQuery, Trans, "set IDENTITY_INSERT " & tblname & " on ")
Util.ExecuteQryNSP(TransCon, CmdType.Text, ExecuteMode.ExecuteNonQuery, Trans, sql3)
Util.ExecuteQryNSP(TransCon, CmdType.Text, ExecuteMode.ExecuteNonQuery, Trans, "set IDENTITY_INSERT " & tblname & " off ")
Else
Util.ExecuteQryNSP(TransCon, CmdType.Text, ExecuteMode.ExecuteNonQuery, Trans, sql3)
End If
Trans.Commit()
Catch ex As Exception
Trans.Rollback()
End Try
'=== Updating the Records from Xml to DataBase
Else
Try
Dim da1 As New SqlDataAdapter
Dim builder As New SqlCommandBuilder(da1)
da1.SelectCommand = New SqlCommand("select * from " & tblname & "", con)
'== Collecting the column names in a string array
Dim str2() As String = str1.Split(",")
'=== Filling the Xml DataSet into the DataTable
Dim dt1 As DataTable = ds2.Tables(index1)
'=== Filling the DataBase dataset into the datatable
Dim dt2 As DataTable = ds1.Tables(index)
Dim drcpu As DataRow
Dim drVendor As DataRow
'=== By Comparing row by row and field by field Updating done
For Each drcpu In dt1.Rows
For Each drVendor In dt2.Rows
If drVendor(str2(0)) = drcpu(str2(0)) Then
For Each Me.str3 In str2
If Not IsDBNull(drcpu(str3)) Then
If drVendor(str3).ToString = drcpu(str3).ToString Then
Continue For
Else
If IsDBNull(drVendor(str3)) Then
drVendor.BeginEdit()
drVendor(str3) = drcpu(str3).ToString
drVendor.EndEdit()
da1.UpdateCommand = New SqlCommand("update " & tblname & " set " & str3 & "='" & Trim(drVendor(str3)) & "' where " & str2(0) & "= " & drVendor(str2(0)) & "")
da1.Update(ds1, "" & tblname & "")
End If
Dim Store2 As String
Dim Store1 As String
Store2 = (UCase(CType(drVendor(str3), String)).Trim)
Store1 = (UCase(CType(drcpu(str3), String)).Trim)
If (Store2).Equals(Store1) Then
Continue For
Else
drVendor.BeginEdit()
drVendor(str3) = drcpu(str3).ToString
drVendor.EndEdit()
Dim SqlStr As String = ""
If tblname = "MasterSettings" Then
SqlStr = "update " & tblname & " set " & str3 & "='" & Replace(Trim(drVendor(str3)), "'", "''") & "' where " & str2(0) & "= " & drVendor(str2(0)) & " and " & str2(1) & "= " & drVendor(str2(1)) & ""
Else
SqlStr = "update " & tblname & " set " & str3 & "='" & Replace(Trim(drVendor(str3)), "'", "''") & "' where " & str2(0) & "= " & drVendor(str2(0)) & ""
End If
da1.UpdateCommand = New SqlCommand(SqlStr)
da1.Update(ds1, "" & tblname & "")
End If
End If
'End If
End If
Next
End If
Next
Next
Catch ex As Exception
MsgBox(ex)
End Try
End If
i += 1
End While
Next
Return True
Catch ex As Exception
Return False
End Try
End Function
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