机房收费系统--组合查询

       本来不打算再发表这些东西的，但是最近帮朝哥调了点机房，感觉这一部分还是有很多精华的，在几个地方思路很好。思路很重要，理清思路可以为后期的实现节省很多时间。毕竟不是自己想出来的，抄袭师哥师姐的东西总归运用不熟练。
       下面是学生基本信息维护的代码。
       这个透明代码好难写。。。

Private Sub cboField_Click(Index As Integer)    If Trim(cboField(0).Text) = "性别" Or Trim(cboField(1).Text) = "性别" Or Trim(cboField(2).Text) = "性别" Then        MsgBox "请在要查询的内容里输入男或女", vbOKOnly + vbExclamation, "提示"    End IfEnd SubPrivate Sub cboField_KeyPress(Index As Integer, KeyAscii As Integer)    KeyAscii = 0End SubPrivate Sub cboOperator_KeyPress(Index As Integer, KeyAscii As Integer)    KeyAscii = 0End SubPrivate Sub cboRelation_KeyPress(Index As Integer, KeyAscii As Integer)    KeyAscii = 0End SubPrivate Sub cmdClean_Click() '清空所有数据    cboField(0).Text = ""    cboField(1).Text = ""    cboField(2).Text = ""    cboOperator(0).Text = ""    cboOperator(1).Text = ""    cboOperator(2).Text = ""    Text1(0).Text = ""    Text1(1).Text = ""    Text1(2).Text = ""    cboRelation(0).Text = ""    cboRelation(1).Text = ""    With MSHFlexGrid1 '添加表头        .CellAlignment = 4        .Rows = 1        .TextMatrix(0, 0) = "学号"        .TextMatrix(0, 1) = "姓名"        .TextMatrix(0, 2) = "卡号"        .TextMatrix(0, 3) = "金额"        .TextMatrix(0, 4) = "系别"        .TextMatrix(0, 5) = "年级"        .TextMatrix(0, 6) = "班级"        .TextMatrix(0, 7) = "性别"        .TextMatrix(0, 8) = "状态"        .TextMatrix(0, 9) = "备注"        .TextMatrix(0, 10) = "类型"        .TextMatrix(0, 11) = "日期"        .TextMatrix(0, 12) = "时间"    End WithEnd SubPrivate Sub cboRelation_Click(Index As Integer)    If Trim(cboRelation(0).Text) <> "" Then '第一个关系不为空时，第二行可用        cboField(1).Enabled = True        cboOperator(1).Enabled = True        Text1(1).Enabled = True        cboRelation(1).Enabled = True    End If    If Trim(cboRelation(1).Text) <> "" Then '第二个关系不为空时，第三行可用        cboField(2).Enabled = True        cboOperator(2).Enabled = True        Text1(2).Enabled = True    End IfEnd SubPrivate Sub cmdExit_Click()    Unload MeEnd SubPrivate Sub cmdInquiry_Click()    Dim txtSQL As String    Dim Msgtext As String    Dim mrc As ADODB.Recordset    '一个条件时    If Trim(cboField(0).Text) = "" Or Trim(cboOperator(0).Text) = "" Or Trim(Text1(0).Text) = "" Then        MsgBox "请将第一行选项填写完整", vbOKOnly + vbExclamation, "提示"        Exit Sub    Else        txtSQL = "select * from student_info where " & Fieldname(cboField(0).Text) & cboOperator(0).Text & "'" & Trim(Text1(0).Text) & "'"    End If    '两个条件时    If cboRelation(0) <> "" Then '判断第一个关系是否选中        If cboField(1).Text = "" Or cboOperator(1).Text = "" Or Text1(1).Text = "" Then            MsgBox "请将第二行选项填写完整", vbOKOnly + vbExclamation, "提示"            Exit Sub        Else            txtSQL = "select * from student_info where " & Fieldname(cboField(0).Text) & cboOperator(0).Text & "'" & Trim(Text1(0).Text) & "'" _            & " " & Relationname(cboRelation(0).Text) & " " & Fieldname(cboField(1).Text) & cboOperator(1).Text & "'" & Trim(Text1(1).Text) & "'"        End If    End If    '三个条件时    If cboRelation(1) <> "" Then '判断第二个关系是否选中        If cboField(2).Text = "" Or cboOperator(2).Text = "" Or Text1(2).Text = "" Then            MsgBox "请将第三行选项填写完整", vbOKOnly + vbExclamation, "提示"            Exit Sub        Else            txtSQL = "select * from student_info where " & Fieldname(cboField(0).Text) & cboOperator(0).Text & "'" & Trim(Text1(0).Text) & "'" _            & " " & Relationname(cboRelation(0).Text) & " " & Fieldname(cboField(1).Text) & cboOperator(1).Text & "'" & Trim(Text1(1).Text) & "'" _            & " " & Relationname(cboRelation(1).Text) & " " & Fieldname(cboField(2).Text) & cboOperator(2).Text & "'" & Trim(Text1(2).Text) & "'"        End If    End If    With MSHFlexGrid1 '添加表头        .CellAlignment = 4        .Rows = 1        .TextMatrix(0, 0) = "学号"        .TextMatrix(0, 1) = "姓名"        .TextMatrix(0, 2) = "卡号"        .TextMatrix(0, 3) = "金额"        .TextMatrix(0, 4) = "系别"        .TextMatrix(0, 5) = "年级"        .TextMatrix(0, 6) = "班级"        .TextMatrix(0, 7) = "性别"        .TextMatrix(0, 8) = "状态"        .TextMatrix(0, 9) = "备注"        .TextMatrix(0, 10) = "类型"        .TextMatrix(0, 11) = "日期"        .TextMatrix(0, 12) = "时间"    End With    Set mrc = ExecuteSQL(txtSQL, Msgtext)    Do While Not mrc.EOF '表内添加信息        With MSHFlexGrid1            .Rows = .Rows + 1            .CellAlignment = 4            .TextMatrix(.Rows - 1, 0) = Trim(mrc.Fields(1))            .TextMatrix(.Rows - 1, 1) = Trim(mrc.Fields(2))            .TextMatrix(.Rows - 1, 2) = Trim(mrc.Fields(0))            .TextMatrix(.Rows - 1, 3) = Trim(mrc.Fields(7))            .TextMatrix(.Rows - 1, 4) = Trim(mrc.Fields(4))            .TextMatrix(.Rows - 1, 5) = Trim(mrc.Fields(5))            .TextMatrix(.Rows - 1, 6) = Trim(mrc.Fields(6))            .TextMatrix(.Rows - 1, 7) = Trim(mrc.Fields(3))            .TextMatrix(.Rows - 1, 8) = Trim(mrc.Fields(10))            .TextMatrix(.Rows - 1, 9) = Trim(mrc.Fields(8))            .TextMatrix(.Rows - 1, 10) = Trim(mrc.Fields(14))            .TextMatrix(.Rows - 1, 11) = Trim(mrc.Fields(12))            .TextMatrix(.Rows - 1, 12) = Trim(mrc.Fields(13))        End With        Call AdjustColWidth(frmBasicInfoMaintain, MSHFlexGrid1)    mrc.MoveNext    Loop    mrc.CloseEnd SubPrivate Sub cmdModify_Click() '选中表内数据    Dim txtSQL As String    Dim Msgtext As String    Dim mrc As ADODB.Recordset    With MSHFlexGrid1        If .RowSel = 0 Then '没有选中时            MsgBox "请选择数据", vbOKOnly + vbExclamation, "提示"            Exit Sub        Else            If .RowSel > 0 Then '查询选中数据                txtSQL = "select * from student_Info where cardno='" & Trim(.TextMatrix(.RowSel, 0)) & "'"                Set mrc = ExecuteSQL(txtSQL, Msgtext)            End If        End If    End With    frmModifySI.ShowEnd SubPrivate Sub Form_Load()    Dim a, b, c    For a = 0 To 2 '字段名里添加信息        With cboField(a)            .AddItem ""            .AddItem "卡号"            .AddItem "学号"            .AddItem "姓名"            .AddItem "性别"            .AddItem "系别"            .AddItem "年级"            .AddItem "班级"        End With    Next a    For b = 0 To 2 '操作符里添加信息        With cboOperator(b)            .AddItem ""            .AddItem "="            .AddItem "<>"            .AddItem "<"            .AddItem ">"        End With    Next b    For c = 0 To 1 '操作符里添加信息        With cboRelation(c)            .AddItem ""            .AddItem "与"            .AddItem "或"        End With    Next c    cboField(1).Enabled = False    cboOperator(1).Enabled = False    Text1(1).Enabled = False    cboField(2).Enabled = False    cboOperator(2).Enabled = False    Text1(2).Enabled = False    cboRelation(1).Enabled = FalseEnd Sub    '定义一个过程，保证可以从数据库选择正确的字段Public Function Fieldname(strFieldname As String) As String    Select Case strFieldname        Case "卡号"            Fieldname = "cardno"        Case "学号"            Fieldname = "studentno"        Case "姓名"                Fieldname = "studentname"        Case "性别"            Fieldname = "sex"        Case "系别"            Fieldname = "department"        Case "年级"            Fieldname = "grade"        Case "班级"            Fieldname = "class"    End SelectEnd FunctionPublic Function Relationname(strRelationname As String) As String    Select Case strRelationname        Case "与"            Relationname = "and"        Case "或"            Relationname = "or"    End SelectEnd Function