这是用vb编的一段关于查询的代码，哪位高手能帮忙加入出错处理的代码吗，就是判断如果数据库中没有这个记录，则出现提示信息。谢谢哪位高手帮忙啊，急！！！！！！！！！！！！！！！！！！！！！！！！



另外哪位高手知道怎么实现只修改数据库的一项，然后把修改的值返回数据库的代码吗，谢谢。





Private Sub cmdInquire_Click()
Dim txtSQL As String
Dim MsgText As String
Dim dd(4) As Boolean
Dim mrc As ADODB.Recordset


txtSQL = "select * from result_Info where "
If Check1(0).Value Then
If Trim(txtSID.Text) = "" Then
sMeg = "学号不能为空"
MsgBox sMeg, vbOKOnly + vbExclamation, "警告"
txtSID.SetFocus
Exit Sub
Else
If Not IsNumeric(Trim(txtSID.Text)) Then
MsgBox "请输入数字！", vbOKOnly + vbExclamation, "警告"
Exit Sub
txtSID.SetFocus
End If
dd(0) = True
txtSQL = txtSQL & "student_ID = '" & Trim(txtSID.Text) & "'"
End If
End If

If Check1(1).Value Then
If Trim(txtName.Text) = "" Then
sMeg = "姓名不能为空"
MsgBox sMeg, vbOKOnly + vbExclamation, "警告"
txtName.SetFocus
Exit Sub
Else
dd(1) = True
If dd(0) Then
txtSQL = txtSQL & "and student_Name = '" & txtName.Text & "'"
Else
txtSQL = txtSQL & "student_Name = '" & txtName.Text & "'"
End If
End If
End If

If Check1(2).Value Then
If Trim(txtCourse.Text) = "" Then
sMeg = "课程不能为空"
MsgBox sMeg, vbOKOnly + vbExclamation, "警告"
txtCourse.SetFocus
Exit Sub
Else
dd(2) = True
If dd(0) Or dd(1) Then
txtSQL = txtSQL & "and course_Name = '" & txtCourse.Text & "'"
Else
txtSQL = txtSQL & "course_Name = '" & txtCourse.Text & "'"
End If
End If
End If

If Not (dd(0) Or dd(1) Or dd(2) Or dd(3)) Then
MsgBox "请设置查询方式！", vbOKOnly + vbExclamation, "警告"
Exit Sub
End If

txtSQL = txtSQL & " order by student_ID "
Set mrc = ExecuteSQL(txtSQL, MsgText)

With myflexgrid
.Rows = 2
.CellAlignment = 4
.TextMatrix(1, 0) = "考试编号"
.TextMatrix(1, 1) = "学号"
.TextMatrix(1, 2) = "姓名"
.TextMatrix(1, 3) = "班号"
.TextMatrix(1, 4) = "课程名称"
.TextMatrix(1, 5) = "分数"


Do While Not mrc.EOF
.Rows = .Rows + 1
.CellAlignment = 4
.TextMatrix(.Rows - 1, 0) = mrc.Fields(0)
.TextMatrix(.Rows - 1, 1) = mrc.Fields(1)
.TextMatrix(.Rows - 1, 2) = mrc.Fields(2)
.TextMatrix(.Rows - 1, 3) = mrc.Fields(3)
.TextMatrix(.Rows - 1, 4) = mrc.Fields(4)
.TextMatrix(.Rows - 1, 5) = mrc.Fields(5)
mrc.MoveNext
Loop

End With

mrc.Close
End Sub