2>数据库级别的事务处理。
需要导入Imports System.Data.SqlClient名称空间。
'This function will add student's infomation and its parent's information concurrently !
'So we should use transaction !
Public Shared Function InsertInfo(ByVal student As clsStudent, ByVal parent As clsParent) As Boolean
Dim success As Boolean = True
Dim cmdStudent As New SqlCommand("insert into student(name,sex,classname) values(@name,@sex,@classname)", cnn)
Dim cmdParent As New SqlCommand("insert into parent(name,sex,salary) values(@name,@sex,@salary)", cnn)
Dim cmdGetStudentid As New SqlCommand("select studentid from student where name=@name ", cnn)
Dim cmdGetParentid As New SqlCommand("select parentid from parent where name=@name", cnn)
Dim cmdStudentParent As New SqlCommand("insert into studentparent(studentid,parentid)values(@studentid,@parentid)", cnn)
cmdStudent.Parameters.Add("@name", student.Name)
cmdStudent.Parameters.Add("@sex", student.Sex)
cmdStudent.Parameters.Add("@classname", student.ClassName)
cmdParent.Parameters.Add("@name", parent.Name)
cmdParent.Parameters.Add("@sex", parent.Sex)
cmdParent.Parameters.Add("@salary", parent.Salary)
cmdGetStudentid.Parameters.Add("@name", student.Name)
cmdGetParentid.Parameters.Add("@name", parent.Name)
Dim transaction As SqlTransaction
Try
cnn.Open()
transaction = cnn.BeginTransaction
cmdStudent.Transaction = transaction
cmdParent.Transaction = transaction
cmdGetStudentid.Transaction = transaction
cmdGetParentid.Transaction = transaction
cmdStudentParent.Transaction = transaction
Dim studentid, parentid As Integer
cmdStudent.ExecuteNonQuery()
cmdParent.ExecuteNonQuery()
studentid = cmdGetStudentid.ExecuteScalar
parentid = cmdGetParentid.ExecuteScalar
cmdStudentParent.Parameters.Add("@studentid", studentid)
cmdStudentParent.Parameters.Add("@parentid", parentid)
cmdStudentParent.ExecuteNonQuery()
transaction.Commit()
Catch ex As Exception
transaction.Rollback()
success = False
MessageBox.Show(ex.Message)
Finally
cnn.Close()
End Try
Return success
End Function
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