Question

使用：

MS-Access 2013 SP1 x86
MS-SQL Server 2012 SP1 CU8 x64
通过ODBC DSN连接，SQL Server驱动程序
UpScene Database Workbench Pro v4.4.4 Pro for MS-SQL Server

My Access 2013应用程序使用SQL Server 2012作为ODBC的后端数据库。我正在使用VBA / ADO来读/写数据到数据库。

到目前为止，我从数据库中检索图像并将其分配给Access窗体上的图像控件时失败了。该映像存储在SQL Server表中（作为VARBINARY（MAX）字段。

在我将字段分配给Image控件时，它会发出运行时错误：“Type notmatch”。图像存储在数据库中作为位图图像。我之前尝试过Jpeg，但是出现了同样的错误。怎么解决这个问题？

SQL Server表定义和存储过程定义：

CREATE TABLE dbo.tbPhoto (
    row_id Int IDENTITY NOT NULL,
    student_id Int NOT NULL,
    picture VarBinary(max),
    date_updated DateTime NOT NULL,
    date_created DateTime NOT NULL, 
    CONSTRAINT PK_tbPhoto PRIMARY KEY CLUSTERED (
      row_id
    )
)

检索图片的访问程序：

Private Sub load_studentdetails(AStudentID As Integer)
 On Error GoTo errhnd

 objStudent.GetStudentDetails AStudentID, StudentDetailsRS

 Set Me.fmStudentReg_DtlA.Form.Recordset = StudentDetailsRS
' Me.fmStudentReg_DtlA.Form.Requery

 objStudent.GetStudentPicture AStudentID, Me.fmStudentReg_DtlA!imgStudentPic

 Exit Sub
errhnd:
 MsgBox "Error: " & Err.Description
End Sub

Public Sub GetStudentPicture(AStudentID As Integer, ByRef APicture As Image)
 On Error GoTo errhnd

 Dim rs As New ADODB.Recordset
 Set cmd.ActiveConnection = GetDBConnection

 cmd.CommandType = adCmdStoredProc
 cmd.CommandText = "dbo.StudentPicture_S"

 cmd.Parameters.Refresh
 cmd(1) = AStudentID

 rs.CursorLocation = adUseClient
 rs.Open cmd

 Set APicture = rs("picture")  '<-----Raises the error: "Type mismatch"

 Exit Sub
errhnd:
 MsgBox "Error: " & Err.Description

End Sub

Answer 1

由于您已经在使用ADODB.Recordset，我建议您使用ADODB.Stream对象作为中介。我刚刚尝试了以下代码，它对我有用：

Option Compare Database
Option Explicit

Private Sub cmdGetPhoto_Click()
    Dim cdb As DAO.Database
    Dim con As ADODB.Connection, rst As ADODB.Recordset, stm As ADODB.Stream

    Set cdb = CurrentDb
    Set con = New ADODB.Connection
    con.Open Mid(cdb.TableDefs("dbo_Clients").Connect, 6)
    Set rst = New ADODB.Recordset
    rst.Open "SELECT Photo FROM Clients WHERE ClientID=1", con, adOpenStatic, adLockOptimistic
    Set stm = New ADODB.Stream
    stm.Type = adTypeBinary
    stm.Open
    stm.Write rst("Photo").Value  ' write bytes to stream
    stm.Position = 0
    Me.Image0.PictureData = stm.Read  ' load bytes into Image control on form

    stm.Close
    Set stm = Nothing
    rst.Close
    Set rst = Nothing
    con.Close
    Set con = Nothing
    Set cdb = Nothing
End Sub

如何从ADO记录集字段将图片加载到MS-Access Image控件？

1 个答案: