class_info.cls

这是个学生信息管理系统

VERSION 1.0 CLASS
BEGIN
  MultiUse = -1  'True
  Persistable = 0  'NotPersistable
  DataBindingBehavior = 0  'vbNone
  DataSourceBehavior  = 0  'vbNone
  MTSTransactionMode  = 0  'NotAnMTSObject
END
Attribute VB_Name = "class_Info"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = True
Attribute VB_PredeclaredId = False
Attribute VB_Exposed = False
Public class_No As Long
Public grade As String
Public director As String
Public classroom_No As Long

Public Sub Init()
  class_No = -1
  grade = ""
  director = -1
  classroom_No = -1
End Sub

'删除class_Info
Public Sub Delete(ByVal TmpId As Long)
  DB_Connect
  
  SqlStmt = "DELETE FROM class_Info WHERE class_No=" + Trim(Str(TmpId))
  OdbcExt (SqlStmt)
  Rc = SQLFreeStmt(Hstmt, SQL_DROP)

  DB_Disconnect
End Sub

Public Sub GetInfo(TmpId As Long)
  class_No = TmpId
  
  DB_Connect
  
  SqlStmt = "SELECT * FROM class_Info WHERE class_No=" + Trim(Str(TmpId))
  OdbcExt (SqlStmt)
  If SQLFetch(Hstmt) <> SQL_NO_DATA_FOUND Then
    '读取部门名称
    ColVal = String(400, 0)
    Rc = SQLGetData(Hstmt, 2, 1, ColVal, Len(ColVal), pcblen)
    grade = TrimStr(ColVal)
    '读取部门描述
    ColVal = String(400, 0)
    Rc = SQLGetData(Hstmt, 3, 1, ColVal, Len(ColVal), pcblen)
    director = TrimStr(ColVal)
    '读取上一级部门的编号
    ColVal = String(40, 0)
    Rc = SQLGetData(Hstmt, 4, 1, ColVal, Len(ColVal), pcblen)
    classroom_No = Val(ColVal)
  Else
    Init
  End If
  Rc = SQLFreeStmt(Hstmt, SQL_DROP)
  
  DB_Disconnect
End Sub

Public Function GetName(ByVal TmpId As Long) As String
  DB_Connect
  
  SqlStmt = "SELECT grade FROM class_Info WHERE class_No=" _
          + Trim(Str(TmpId))
  OdbcExt (SqlStmt)
  If SQLFetch(Hstmt) <> SQL_NO_DATA_FOUND Then
    ColVal = String(400, 0)
    Rc = SQLGetData(Hstmt, 1, 1, ColVal, Len(ColVal), pcblen)
    GetName = TrimStr(ColVal)
  Else
    GetName = ""
  End If
  Rc = SQLFreeStmt(Hstmt, SQL_DROP)
  
  DB_Disconnect
End Function

Public Function GetNewId() As Long
  Dim TmpId As Long
  
  DB_Connect
    
  SqlStmt = "SELECT class_No FROM class_Info ORDER BY class_No"
  OdbcExt (SqlStmt)
  i = 1
  Do While SQLFetch(Hstmt) <> SQL_NO_DATA_FOUND
    ColVal = String(40, 0)
    Rc = SQLGetData(Hstmt, 1, 1, ColVal, Len(ColVal), pcblen)
    TmpId = Val(ColVal)
    If TmpId = i Then
      i = i + 1
    Else
      GetNewId = i
      Rc = SQLFreeStmt(Hstmt, SQL_DROP)
      DB_Disconnect
      Exit Function
    End If
  Loop
  Rc = SQLFreeStmt(Hstmt, SQL_DROP)
  
  DB_Disconnect
  
  GetNewId = i
End Function

Public Function HaveEmp(ByVal TmpDepid As Long) As Boolean
  DB_Connect
  
  SqlStmt = "SELECT * FROM Employees WHERE class_No=" + Trim(Str(TmpDepid))
  OdbcExt (SqlStmt)
  If SQLFetch(Hstmt) = SQL_NO_DATA_FOUND Then
    HaveEmp = False
  Else
    HaveEmp = True
  End If
  Rc = SQLFreeStmt(Hstmt, SQL_DROP)
  
  DB_Disconnect
End Function

Public Function HaveSon(ByVal Tmpclassroom_No As Long) As Boolean
  DB_Connect
  
  SqlStmt = "SELECT class_No FROM class_Info WHERE classroom_No=" _
          + Trim(Str(Tmpclassroom_No))
  OdbcExt (SqlStmt)
  If SQLFetch(Hstmt) = SQL_NO_DATA_FOUND Then
    HaveSon = False
  Else
    HaveSon = True
  End If
  Rc = SQLFreeStmt(Hstmt, SQL_DROP)
  
  DB_Disconnect
End Function

Public Function In_DB(ByVal DepName As String, _
                      ByVal DepUpper As Long) As Boolean
  DB_Connect
  
  SqlStmt = "SELECT class_No FROM class_Info WHERE grade='" + Trim(DepName) _
             + "' and classroom_No=" + Trim(Str(DepUpper))
  OdbcExt (SqlStmt)
  If SQLFetch(Hstmt) = SQL_NO_DATA_FOUND Then
    In_DB = False
  Else
    In_DB = True
  End If
  Rc = SQLFreeStmt(Hstmt, SQL_DROP)

  DB_Disconnect
End Function

Public Function Insert() As Long
 ' Dim class_No As Long
  '生成新的编号
  'class_No = GetNewId
  
  DB_Connect
  SqlStmt = "INSERT INTO class_Info VALUES(" + Trim(Str(class_No)) + ",'" _
            + Trim(grade) + "','" + Trim(director) _
            + "','" + Trim(Str(classroom_No)) + "')"
  OdbcExt (SqlStmt)
  Rc = SQLFreeStmt(Hstmt, SQL_DROP)
  DB_Disconnect
  Insert = class_No
End Function

Public Sub Load_class_Info_ByUpper(classroom_No As Long)
  Dim i As Integer
  '初始化部门数组
  Erase Arr_DepName
  Erase Arr_Depdirector
  Erase Arr_DepId
  ReDim Arr_DepName(0)
 
  ReDim Arr_DepId(0)
  
  DB_Connect
  SqlStmt = "SELECT class_No,grade,director FROM class_Info WHERE classroom_No=" _
          + Trim(Str(classroom_No)) + " ORDER BY class_No"
  OdbcExt (SqlStmt)
  i = 0
  Do Until SQLFetch(Hstmt) = 100
    '读取部门编号
    ColVal = String(40, 0)
    Rc = SQLGetData(Hstmt, 1, 1, ColVal, Len(ColVal), pcblen)
    ReDim Preserve Arr_DepId(i + 1)
    Arr_DepId(i) = Val(ColVal)
    '读取部门名称
    ColVal = String(400, 0)
    Rc = SQLGetData(Hstmt, 2, 1, ColVal, Len(ColVal), pcblen)
    ReDim Preserve Arr_DepName(i + 1)
    Arr_DepName(i) = TrimStr(ColVal)
    '读取部门描述
    ColVal = String(400, 0)
    Rc = SQLGetData(Hstmt, 3, 1, ColVal, Len(ColVal), pcblen)

    Arr_Depdirector(i) = Val(ColVal)
    
    i = i + 1
  Loop
  Rc = SQLFreeStmt(Hstmt, SQL_DROP)
  
  DB_Disconnect
End Sub

'更新数据
Public Sub Update(ByVal TmpId As Long)
  DB_Connect
  
  SqlStmt = "UPDATE class_Info SET grade='" + Trim(grade) _
          + "',director='" + Trim(director) _
          + "',classroom_No='" + Trim(classroom_No) + "' WHERE class_No=" + Trim(Str(TmpId))
  OdbcExt (SqlStmt)
  Rc = SQLFreeStmt(Hstmt, SQL_DROP)
  DB_Disconnect
End Sub