所有形式的 VB.NET 连接

Question

如何仅使用一次设置数据库连接所有表单？

现在发生在我身上的是我制作的每个表格我总是把我的数据库连接

Answer 1

创建一个模块并创建一个可以从任何地方调用的共享函数。

将数据获取到您的数据集，从您项目中的任何地方调用它

        Try
            Dim dsEmployee As New DataSet()
            dsEmployee = ExecuteDataSet("select * from tblEmployee")
        Catch ex As Exception
            MessageBox.Show("Getting error while getting dataset. " + ex.Message.ToString(), "Data Base", MessageBoxButtons.OK, MessageBoxIcon.Error)
        End Try

用于将记录插入到您的数据库

ExecuteNonQuery("insert into tblEmployee(Emp_ID,Emp_Code,Emp_Name,Emp_Mobile)values(1,'EMP1','Anand','+91 98000000')")

创建一个模块并制作所有必需的功能并将您的数据库连接字符串放入MyConnection字符串中

Option Explicit On
Imports System.Data.SqlClient
Module dbConnect
Dim MyConnection As String = "data source=MyPc;Initial Catalog=TestDb;User ID=sa;Password=12345;"

    Public Function ExecuteDataSet(ByVal _Query As String) As DataSet
        Dim dsReturn As New DataSet
        Try
            Dim conn As String = MyConnection
            Using con = New SqlConnection(conn)
                con.Open()
                Dim cmd1 As New SqlCommand(_Query)
                cmd1.Connection = con
                Dim da As New SqlDataAdapter(cmd1)
                dsReturn = New DataSet
                da.Fill(dsReturn)
                con.Close()
            End Using
        Catch ex As Exception
            MessageBox.Show("Error While Getting DataSet :" + vbNewLine + ex.Message.ToString(), " ERROR ", MessageBoxButtons.OK, MessageBoxIcon.Error)
        End Try
        Return dsReturn
    End Function

    Public Function ExecuteNonQuery(ByVal _Query As String) As Integer
        Dim res As Integer = 0
        Try
            Dim conn As String = MyConnection
            Using con = New SqlConnection(conn)
                Dim cmd = New SqlCommand()
                cmd.Connection = con
                con.Open()
                cmd.CommandText = _Query
                cmd.Connection = con
                res = cmd.ExecuteNonQuery
                con.Close()
            End Using
        Catch ex As Exception
            MessageBox.Show("Error While Inserting Records :" + vbNewLine + ex.Message.ToString(), " ERROR ", MessageBoxButtons.OK, MessageBoxIcon.Error)
        End Try
        Return res
    End Function

End Module