sql - 如何将表格行详细信息复制到 Visual Studio 表单

Question

我有一个表试试 - “uid、pwd、mob 和名称。”

CL001 abc 9876589 admin
CL002 def 8909898 admin2

我想从表中以视觉基本形式调用值并在相应的文本框中显示值。我知道这个 SQL 查询 -->select * from try where uid="CL001"

Answer 1

这是一个允许您在数据库上执行 SELECT 语句的函数。在调用它之前，您必须声明一个新的数据表，例如：

Dim dt as New DataTable
dt = doSQL("select * from try where uid='CL001'")

    Public Function DoSQL(ByVal sqlCmd As String) As DataTable
    Dim cmd As New SQL.SqlCommand()
    Dim cnn As New SQL.SqlConnection(My.Settings.cnnString) ' your connection string here
    Dim sqlDT As New DataTable
    With cmd
        .Connection = cnn
        .CommandText = sqlCmd
        .CommandType = CommandType.Text
    End With
    Dim da As New SQL.SqlDataAdapter()
    da.SelectCommand = cmd
    da.Fill(sqlDT)

    Return sqlDT

End Function

数据表将具有匹配的记录。因此，如果您知道只有 1 条记录，您可以执行以下操作：

textbox.text = dt.Rows(0).Item("uid").ToString

或者你可以将它绑定到一个文本框并使用 bindingmanagerbase 来跟踪你喜欢的位置：

Private WithEvents bm As BindingManagerBase ' Class scope

Private Sub partBind(ByVal dt As DataTable)
txtBox.DataBindings.Add("Text", dt, "uid")
End Sub

然后，您可以使用 bm.position 控制翻转记录，如下所示：

Private Sub btnNavClick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnNext.Click, btnPrevious.Click, btnLast.Click, btnFirst.Click
    Dim btnClicked As Button = DirectCast(sender, Button)

    Select Case btnClicked.Name
        Case "btnNext"
            If bm.Position < bm.Count - 1 Then
                bm.Position += 1
            Else
                bm.Position = 0
            End If

        Case "btnPrevious"
            If bm.Position > 0 Then
                bm.Position -= 1
            Else
                bm.Position = bm.Count
            End If
            bm.Position -= 0
        Case "btnLast"
            bm.Position = bm.Count
        Case "btnFirst"
            bm.Position = 0
    End Select

End Sub