使用VB.NET中的多个复选框过滤MySql数据库

Question

我希望通过组合多个复选框和文本框查询来过滤存储在MySql数据库中的数据。您可以在此处找到表单的屏幕截图：

搜索表格：

TABLES：

PROJECTS TABLE

DETAILS TABLE

PS：“项目”表中只有ID字段是唯一的！

如果用户在这三个文本框中的任何一个中写入，则文本框的其余部分将变空。目前它使用文本框工作。我想将搜索条件与复选框结合起来。

假设用户在TEXTBOX1中写入并从复选框中选择FAS，VAPA和ACC，结果应该列在我的列表视图框中。

这是我到目前为止的代码：

    Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click

    If TextBox1.Text = "" And TextBox2.Text = "" And TextBox3.Text = "" Then
        MsgBox("Bir arama kriteri girin!", MsgBoxStyle.Critical, "UYARI!")
        Exit Sub
    End If


        ListView1.Items.Clear()

        If TextBox1.Text <> "" Then
                Dim cmd As New MySqlCommand
                Dim ad As New MySqlDataAdapter
                Dim projeadi As String = "select projects.ID, projects.PROJEADI, projects.TEKLIFFIRMA, details.ID, details.MARKA from projects INNER JOIN details ON projects.ID = details.ID WHERE PROJEADI='" & TextBox1.Text & "';"
                Dim tbl As New DataTable
                Dim i As Integer
                With cmd
                    .CommandText = projeadi
                    .Connection = con
                End With
                With ad
                    .SelectCommand = cmd
                    .Fill(tbl)
                End With

                For i = 0 To tbl.Rows.Count - 1
                    With ListView1
                        .Items.Add(tbl.Rows(i)("ID"))
                        With .Items(.Items.Count - 1).SubItems
                            .Add(tbl.Rows(i)("PROJEADI"))
                            .Add(tbl.Rows(i)("TEKLIFFIRMA"))
                            .Add(tbl.Rows(i)("MARKA"))
                        End With
                    End With
                Next

        ElseIf TextBox2.Text <> "" Then
            Dim cmd As New MySqlCommand
            Dim ad As New MySqlDataAdapter
            Dim tekliffirma As String = "select projects.ID, projects.PROJEADI, projects.TEKLIFFIRMA, details.ID, details.MARKA from projects INNER JOIN details ON projects.ID = details.ID WHERE TEKLIFFIRMA='" & TextBox2.Text & "';"
            Dim tbl As New DataTable
            Dim i As Integer
            With cmd
                .CommandText = tekliffirma
                .Connection = con
            End With
            With ad
                .SelectCommand = cmd
                .Fill(tbl)
            End With

            For i = 0 To tbl.Rows.Count - 1
                With ListView1
                    .Items.Add(tbl.Rows(i)("ID"))
                    With .Items(.Items.Count - 1).SubItems
                        .Add(tbl.Rows(i)("PROJEADI"))
                        .Add(tbl.Rows(i)("TEKLIFFIRMA"))
                        .Add(tbl.Rows(i)("MARKA"))
                    End With
                End With
            Next
        ElseIf TextBox3.Text <> "" Then
            Dim cmd As New MySqlCommand
            Dim ad As New MySqlDataAdapter
            Dim marka As String = "select projects.ID, projects.PROJEADI, projects.TEKLIFFIRMA, details.ID, details.MARKA from projects INNER JOIN details ON projects.ID = details.ID WHERE MARKA='" & TextBox3.Text & "';"
            Dim tbl As New DataTable
            Dim i As Integer
            With cmd
                .CommandText = marka
                .Connection = con
            End With
            With ad
                .SelectCommand = cmd
                .Fill(tbl)
            End With

            For i = 0 To tbl.Rows.Count - 1
                With ListView1
                    .Items.Add(tbl.Rows(i)("ID"))
                    With .Items(.Items.Count - 1).SubItems
                        .Add(tbl.Rows(i)("PROJEADI"))
                        .Add(tbl.Rows(i)("TEKLIFFIRMA"))
                        .Add(tbl.Rows(i)("MARKA"))
                    End With
                End With
            Next
        End If

请告知。

谢谢。

奥古兹

Answer 1

好吧，因为我不知道对应于复选框过滤条件的表格字段的名称，我假设它是Projects.Sistem

我会将所有复选框分组到GroupBox中，以便使用For循环来检查所有复选框。如果选中其中任何一个，则会在SQL语句的末尾添加AND子句。

完成后，另一个For将检查每个选中的CheckBox，将复选框的Name添加到最终的SQL语句中，以获取这样的SQL语句

SELECT projects.ID, projects.PROJEADI, projects.TEKLIFFIRMA, details.ID,
details.MARKA from projects INNER JOIN details ON projects.ID = details.ID
WHERE ..... AND Projects.Sistem IN ('FAS', 'VAPA', 'CCTV',.....)

以下代码只是一个近似值。您需要检查它并使其适应您现有的代码

Dim SQL As String = ""

If projeadi <> "" Then
   SQL = projeadi
End If

If tekliffirma <> "" Then
   SQL = tekliffirma
End If

If marka <> "" Then
   SQL = marka
End If

For Each chkBox As CheckBox in GroupBox1.Controls
   If chkBox.Checked = True Then
      SQL = SQL & " AND Project.Sistem IN ( "
      Exit For
   End if
Next
For Each chkBox As CheckBox In GroupBox1.Controls
    If chkBox.Checked = True Then
         Sql = Sql & "'" & chkBox.Name & "',"
    End If
Next
Sql = Sql.Substring(0, Sql.Length - 1)
Sql = Sql & ")"