在连接到 sqlserver 期间 System.Windows.Forms.dll 中发生类型 'System.StackOverflowException' 的未处理异常
An unhandled exception of type 'System.StackOverflowException' occurred in System.Windows.Forms.dll during connect to sqlserver
需要有关此错误的帮助，无法找出问题所在..
` 进口 System.Windows.Forms
进口 System.Data.Sql
导入 System.Data.Sql 客户端
进口 System.Configuration
Public Class Celclass
Dim conn As SqlConnection
Dim cmd, cmd1, cmd2, cmd3 As SqlCommand
Dim da, da1, da2, da3 As SqlDataAdapter
Dim ds, ds1, ds2, ds3 As DataSet
Dim dt, dt1, dt2, dt3 As DataTable
Dim dr, dr1, dr2, dr3 As DataRow
Dim scb, scb1, scb2, scb3 As SqlCommandBuilder
Public Sub conn1(ByVal sql As String, ByVal dsname As String)
conn = New SqlConnection()
conn.ConnectionString = ConfigurationManager.AppSettings("ConnectionString")
cmd = New SqlCommand(sql, conn)
da = New SqlDataAdapter
da.SelectCommand = cmd
ds = New DataSet
da.Fill(ds, dsname)
End Sub
Public Sub conn2(ByVal sql As String, ByVal dsname As String)
conn = New SqlConnection()
conn.ConnectionString = ConfigurationManager.AppSettings("ConnectionString")
cmd1 = New SqlCommand(sql, conn)
da1 = New SqlDataAdapter
da1.SelectCommand = cmd1
ds1 = New DataSet
da1.Fill(ds1, dsname)
End Sub
Public Sub conn3(ByVal sql As String, ByVal dsname As String)
conn = New SqlConnection()
conn.ConnectionString = ConfigurationManager.AppSettings("ConnectionString")
cmd2 = New SqlCommand(sql, conn)
da2 = New SqlDataAdapter
da2.SelectCommand = cmd2
ds2 = New DataSet
da2.Fill(ds2, dsname)
End Sub
Public Sub conn4(ByVal sql As String, ByVal dsname As String)
conn = New SqlConnection()
conn.ConnectionString = ConfigurationManager.AppSettings("ConnectionString")
cmd3 = New SqlCommand(sql, conn)
da3 = New SqlDataAdapter
da3.SelectCommand = cmd3
ds3 = New DataSet
da3.Fill(ds3, dsname)
End Sub
Public Sub clear()
txtPart.ReadOnly = True
txtMpn.ReadOnly = True
txtdc.ReadOnly = True
txtQty.ReadOnly = True
txtPO.ReadOnly = True
cmbCoo.SelectedIndex = -1
cmbCoo.Text = ""
txtPart.Text = ""
txtMpn.Text = ""
txtBatch.Text = ""
txtdc.Text = ""
txtQty.Text = ""
txtPO.Text = ""
chk.Checked = False
End Sub
Private Sub txtJob_TextChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles txtJob.TextChanged
txtJob.Text = Trim(txtJob.Text)
conn1("select p.qty, p.lot, p.mpn, p.dc1, p.dc2, p.dc3, s.raw, s.so_raw, s.prog, s.po, p.job_no from prod_pt p inner join pln_so s on p.so_id=s.so_id where p.job_no='" & txtJob.Text & "'", "pt")
If ds.Tables("pt").Rows.Count > 0 Then
dr = ds.Tables("pt").Rows(0)
If dr("po") = "" Then
MsgBox("No PO Key in!")
txtJob.Text = ""
Exit Sub
End If
Dim fulldc As String = ""
fulldc = fulldc + dr("dc1")
If UCase(dr("dc2")) <> "NA" And dr("dc2") <> "" Then
fulldc = fulldc + "/" + dr("dc2")
End If
If UCase(dr("dc3")) <> "NA" And dr("dc3") <> "" Then
fulldc = fulldc + "/" + dr("dc3")
End If
txtJob.Text = UCase(dr("job_no"))
If dr("prog").Equals(System.DBNull.Value) = False Then
If dr("prog") <> "" Then
txtPart.Text = UCase(dr("prog"))
Else
txtPart.Text = UCase(dr("so_raw"))
End If
Else
txtPart.Text = UCase(dr("so_raw"))
End If
txtMpn.Text = UCase(dr("mpn"))
txtdc.Text = fulldc
txtQty.Text = dr("qty")
txtPO.Text = UCase(dr("po"))
txtBatch.Focus()
End If
End Sub
Private Sub btnCancel_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnCancel.Click
Dim m As Form
m = Main
Me.Close()
m.Show()
End Sub
Private Sub btnEdit_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnEdit.Click
txtPart.ReadOnly = False
txtMpn.ReadOnly = False
txtdc.ReadOnly = False
txtQty.ReadOnly = False
txtPO.ReadOnly = False
End Sub
Public Sub insert(ByVal qty As String)
Dim x As Integer
Dim coo As String
If chk.Checked = True Then
x = 2
Else
x = 1
End If
If cmbCoo.Text = "GERMANY" Then
coo = "DE"
ElseIf cmbCoo.Text = "JAPAN" Then
coo = "JP"
ElseIf cmbCoo.Text = "MALAYSIA" Then
coo = "MY"
ElseIf cmbCoo.Text = "PAPUA NEW GUINEA" Then
coo = "PG"
ElseIf cmbCoo.Text = "SINGAPORE" Then
coo = "SG"
ElseIf cmbCoo.Text = "UNITED STATES" Then
coo = "US"
Else
coo = cmbCoo.Text
End If
For i As Integer = 1 To x
conn4("select * from label_celclass", "insert")
dt3 = ds3.Tables("insert")
dr3 = dt3.NewRow
dr3("part") = txtPart.Text
dr3("mpn") = txtMpn.Text
dr3("batch") = txtBatch.Text
dr3("dc") = txtdc.Text
dr3("qty") = qty
dr3("po") = txtPO.Text
dr3("coo") = coo
dt3.Rows.Add(dr3)
scb3 = New SqlCommandBuilder(da3)
da3.InsertCommand = scb3.GetInsertCommand
da3.Update(ds3, "insert")
ds3.AcceptChanges()
Next
End Sub
Public Sub delete()
Dim con As SqlConnection = New SqlConnection(ConfigurationManager.AppSettings("ConnectionString"))
Dim str As String = "DELETE FROM label_celclass"
Dim cmd As SqlCommand = New SqlCommand(str, con)
con.Open()
cmd.ExecuteNonQuery()
con.Close()
End Sub
Public Sub printing()
conn1("select * from label_celclass", "others")
Dim retval
retval = Shell(Config.BarTenderFile & " /F=C:\barcode\cele.btw /P /X", vbMinimizedFocus)
'telford
'retval = Shell("C:\Program Files\Seagull\BarTender 6.20\Enterprise\bartend.exe /F=C:\barcode\cele.btw /P /X", vbMinimizedFocus)
'cele
'retval = Shell("C:\Program Files\Seagull\BarTender.75\bartend.exe /F=C:\barcode\cele.btw /P /X", vbMinimizedFocus)
'jabil
'retval = Shell("C:\Program Files\Seagull\BarTender.00\bartend.exe /F=C:\barcode\cele.btw /P /X", vbMinimizedFocus)
End Sub
Private Sub btnPrint_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnPrint.Click
If txtBatch.Text = "" Then
MsgBox("Please key in Batch No")
txtBatch.Focus()
Exit Sub
End If
If cmbCoo.Text = "" Then
MsgBox("Please select COO")
cmbCoo.Focus()
Exit Sub
End If
Dim qty, part, reel As Integer
delete()
conn1("select * from production_oqc where job_no='" & txtJob.Text & "' and status='Accept'", "oqc")
If ds.Tables("oqc").Rows.Count > 0 Then 'oqc record found
For i As Integer = 0 To ds.Tables("oqc").Rows.Count - 1
dr = ds.Tables("oqc").Rows(i)
qty = dr("qty_per_reel")
insert(CStr(qty))
Next
Else 'no oqc record found
conn2("select s.fa_ref_no, s.revision, s.pkg, s.lead from pln_so s inner join prod_pt p on s.so_id=p.so_id where p.job_no='" & txtJob.Text & "'", "fa")
dr1 = ds1.Tables("fa").Rows(0)
If dr1("fa_ref_no") <> "" Then 'get from fa taping
conn3("select * from fa_taping where fa_ref_no='" & dr1("fa_ref_no") & "' and revision='" & dr1("revision") & "'", "taping")
If ds2.Tables("taping").Rows.Count > 0 Then 'fa taping record found
dr2 = ds2.Tables("taping").Rows(0)
qty = dr2("qty_per_reel")
If CInt(txtQty.Text) > qty Then 'more than 1 reel
part = CInt(txtQty.Text) Mod qty
reel = (CInt(txtQty.Text) - part) / qty
For j As Integer = 0 To reel - 1
insert(CStr(qty))
Next
If part <> 0 Then
insert(CStr(part))
End If
Else
insert(txtQty.Text)
End If
Else 'no fa taping record found, use fa taping mast
conn4("select * from fa_taping_mast where pkg='" & dr1("pkg") & "' and lead='" & dr1("lead") & "' and status='Approved'", "mast")
If ds3.Tables("mast").Rows.Count > 0 Then 'fa taping mast record found
dr3 = ds3.Tables("mast").Rows(0)
qty = dr3("qty_per_reel")
If CInt(txtQty.Text) > qty Then 'more than 1 reel
part = CInt(txtQty.Text) Mod qty
reel = (CInt(txtQty.Text) - part) / qty
For k As Integer = 0 To reel - 1
insert(CStr(qty))
Next
If part <> 0 Then
insert(CStr(part))
End If
Else
insert(txtQty.Text)
End If
Else 'no fa taping mast record found
insert(txtQty.Text)
End If
End If
Else 'get from fa taping mast
conn3("select * from fa_taping_mast where pkg='" & dr1("pkg") & "' and lead='" & dr1("lead") & "' and status='Approved'", "taping_mast")
If ds2.Tables("taping_mast").Rows.Count > 0 Then 'fa taping mast record found
dr2 = ds2.Tables("taping_mast").Rows(0)
qty = dr2("qty_per_reel")
If CInt(txtQty.Text) > qty Then 'more than 1 reel
part = CInt(txtQty.Text) Mod qty
reel = (CInt(txtQty.Text) - part) / qty
For l As Integer = 0 To reel - 1
insert(CStr(qty))
Next
If part <> 0 Then
insert(CStr(part))
End If
Else '1 reel
insert(txtQty.Text)
End If
Else 'no fa taping mast record found
insert(txtQty.Text)
End If
End If
End If
printing()
clear()
txtJob.Text = ""
txtJob.Focus()
End Sub
Private Sub btnPaper_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnPaper.Click
Dim p As Form
p = Celclass_papertaping
Me.Close()
p.Show()
End Sub
结束Class
错误
Private Sub txtJob_TextChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles txtJob.TextChanged
conn1("select p.qty, p.lot, p.mpn, p.dc1, p.dc2, p.dc3, s.raw, s.so_raw, s.prog, s.po, p.job_no from prod_pt p inner join pln_so s on p.so_id=s.so_id where p.job_no='" & txtJob.Text & "'", "pt")
精简到最简单的级别，您将得到一个 WhosebugException，因为您正在其自己的 TextChanged 事件处理程序中更改 txtJob.Text。所以最终发生的是：
- 用户在
txtJob 中输入了一些内容。
- 引发了
txtJob.TextChanged 事件。
- 您的
txtJob_TextChanged 事件处理程序被调用。
- 在
txtJob_TextChanged 内，您的代码更改 txtJob.Text。
- 引发了
txtJob.TextChanged 事件。
- 重复3-6直到堆栈溢出。
解决方法是添加一个 Boolean 标志，指示代码仍在处理文本更改：
Private _istxtJobProcessing As Boolean
Private Sub txtJob_TextChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles txtJob.TextChanged
'If we're already processing, bail out now.
If _istxtJobProcessing Then Return
'Set a flag so that we know that we are already processing.
_istxtjobProcessing = True
' Now run your code here...
' And afterward, reset the flag.
_istxtJobProcessing = False
End Sub
您还应注意，您正在编写的 SQL 代码容易受到 SQL injection 的攻击。如果您搜索该主题，您会在 VB.NET.
中找到大量关于如何使用参数化查询避免这种情况的答案
需要有关此错误的帮助，无法找出问题所在..
` 进口 System.Windows.Forms 进口 System.Data.Sql 导入 System.Data.Sql 客户端 进口 System.Configuration
Public Class Celclass
Dim conn As SqlConnection
Dim cmd, cmd1, cmd2, cmd3 As SqlCommand
Dim da, da1, da2, da3 As SqlDataAdapter
Dim ds, ds1, ds2, ds3 As DataSet
Dim dt, dt1, dt2, dt3 As DataTable
Dim dr, dr1, dr2, dr3 As DataRow
Dim scb, scb1, scb2, scb3 As SqlCommandBuilder
Public Sub conn1(ByVal sql As String, ByVal dsname As String)
conn = New SqlConnection()
conn.ConnectionString = ConfigurationManager.AppSettings("ConnectionString")
cmd = New SqlCommand(sql, conn)
da = New SqlDataAdapter
da.SelectCommand = cmd
ds = New DataSet
da.Fill(ds, dsname)
End Sub
Public Sub conn2(ByVal sql As String, ByVal dsname As String)
conn = New SqlConnection()
conn.ConnectionString = ConfigurationManager.AppSettings("ConnectionString")
cmd1 = New SqlCommand(sql, conn)
da1 = New SqlDataAdapter
da1.SelectCommand = cmd1
ds1 = New DataSet
da1.Fill(ds1, dsname)
End Sub
Public Sub conn3(ByVal sql As String, ByVal dsname As String)
conn = New SqlConnection()
conn.ConnectionString = ConfigurationManager.AppSettings("ConnectionString")
cmd2 = New SqlCommand(sql, conn)
da2 = New SqlDataAdapter
da2.SelectCommand = cmd2
ds2 = New DataSet
da2.Fill(ds2, dsname)
End Sub
Public Sub conn4(ByVal sql As String, ByVal dsname As String)
conn = New SqlConnection()
conn.ConnectionString = ConfigurationManager.AppSettings("ConnectionString")
cmd3 = New SqlCommand(sql, conn)
da3 = New SqlDataAdapter
da3.SelectCommand = cmd3
ds3 = New DataSet
da3.Fill(ds3, dsname)
End Sub
Public Sub clear()
txtPart.ReadOnly = True
txtMpn.ReadOnly = True
txtdc.ReadOnly = True
txtQty.ReadOnly = True
txtPO.ReadOnly = True
cmbCoo.SelectedIndex = -1
cmbCoo.Text = ""
txtPart.Text = ""
txtMpn.Text = ""
txtBatch.Text = ""
txtdc.Text = ""
txtQty.Text = ""
txtPO.Text = ""
chk.Checked = False
End Sub
Private Sub txtJob_TextChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles txtJob.TextChanged
txtJob.Text = Trim(txtJob.Text)
conn1("select p.qty, p.lot, p.mpn, p.dc1, p.dc2, p.dc3, s.raw, s.so_raw, s.prog, s.po, p.job_no from prod_pt p inner join pln_so s on p.so_id=s.so_id where p.job_no='" & txtJob.Text & "'", "pt")
If ds.Tables("pt").Rows.Count > 0 Then
dr = ds.Tables("pt").Rows(0)
If dr("po") = "" Then
MsgBox("No PO Key in!")
txtJob.Text = ""
Exit Sub
End If
Dim fulldc As String = ""
fulldc = fulldc + dr("dc1")
If UCase(dr("dc2")) <> "NA" And dr("dc2") <> "" Then
fulldc = fulldc + "/" + dr("dc2")
End If
If UCase(dr("dc3")) <> "NA" And dr("dc3") <> "" Then
fulldc = fulldc + "/" + dr("dc3")
End If
txtJob.Text = UCase(dr("job_no"))
If dr("prog").Equals(System.DBNull.Value) = False Then
If dr("prog") <> "" Then
txtPart.Text = UCase(dr("prog"))
Else
txtPart.Text = UCase(dr("so_raw"))
End If
Else
txtPart.Text = UCase(dr("so_raw"))
End If
txtMpn.Text = UCase(dr("mpn"))
txtdc.Text = fulldc
txtQty.Text = dr("qty")
txtPO.Text = UCase(dr("po"))
txtBatch.Focus()
End If
End Sub
Private Sub btnCancel_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnCancel.Click
Dim m As Form
m = Main
Me.Close()
m.Show()
End Sub
Private Sub btnEdit_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnEdit.Click
txtPart.ReadOnly = False
txtMpn.ReadOnly = False
txtdc.ReadOnly = False
txtQty.ReadOnly = False
txtPO.ReadOnly = False
End Sub
Public Sub insert(ByVal qty As String)
Dim x As Integer
Dim coo As String
If chk.Checked = True Then
x = 2
Else
x = 1
End If
If cmbCoo.Text = "GERMANY" Then
coo = "DE"
ElseIf cmbCoo.Text = "JAPAN" Then
coo = "JP"
ElseIf cmbCoo.Text = "MALAYSIA" Then
coo = "MY"
ElseIf cmbCoo.Text = "PAPUA NEW GUINEA" Then
coo = "PG"
ElseIf cmbCoo.Text = "SINGAPORE" Then
coo = "SG"
ElseIf cmbCoo.Text = "UNITED STATES" Then
coo = "US"
Else
coo = cmbCoo.Text
End If
For i As Integer = 1 To x
conn4("select * from label_celclass", "insert")
dt3 = ds3.Tables("insert")
dr3 = dt3.NewRow
dr3("part") = txtPart.Text
dr3("mpn") = txtMpn.Text
dr3("batch") = txtBatch.Text
dr3("dc") = txtdc.Text
dr3("qty") = qty
dr3("po") = txtPO.Text
dr3("coo") = coo
dt3.Rows.Add(dr3)
scb3 = New SqlCommandBuilder(da3)
da3.InsertCommand = scb3.GetInsertCommand
da3.Update(ds3, "insert")
ds3.AcceptChanges()
Next
End Sub
Public Sub delete()
Dim con As SqlConnection = New SqlConnection(ConfigurationManager.AppSettings("ConnectionString"))
Dim str As String = "DELETE FROM label_celclass"
Dim cmd As SqlCommand = New SqlCommand(str, con)
con.Open()
cmd.ExecuteNonQuery()
con.Close()
End Sub
Public Sub printing()
conn1("select * from label_celclass", "others")
Dim retval
retval = Shell(Config.BarTenderFile & " /F=C:\barcode\cele.btw /P /X", vbMinimizedFocus)
'telford
'retval = Shell("C:\Program Files\Seagull\BarTender 6.20\Enterprise\bartend.exe /F=C:\barcode\cele.btw /P /X", vbMinimizedFocus)
'cele
'retval = Shell("C:\Program Files\Seagull\BarTender.75\bartend.exe /F=C:\barcode\cele.btw /P /X", vbMinimizedFocus)
'jabil
'retval = Shell("C:\Program Files\Seagull\BarTender.00\bartend.exe /F=C:\barcode\cele.btw /P /X", vbMinimizedFocus)
End Sub
Private Sub btnPrint_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnPrint.Click
If txtBatch.Text = "" Then
MsgBox("Please key in Batch No")
txtBatch.Focus()
Exit Sub
End If
If cmbCoo.Text = "" Then
MsgBox("Please select COO")
cmbCoo.Focus()
Exit Sub
End If
Dim qty, part, reel As Integer
delete()
conn1("select * from production_oqc where job_no='" & txtJob.Text & "' and status='Accept'", "oqc")
If ds.Tables("oqc").Rows.Count > 0 Then 'oqc record found
For i As Integer = 0 To ds.Tables("oqc").Rows.Count - 1
dr = ds.Tables("oqc").Rows(i)
qty = dr("qty_per_reel")
insert(CStr(qty))
Next
Else 'no oqc record found
conn2("select s.fa_ref_no, s.revision, s.pkg, s.lead from pln_so s inner join prod_pt p on s.so_id=p.so_id where p.job_no='" & txtJob.Text & "'", "fa")
dr1 = ds1.Tables("fa").Rows(0)
If dr1("fa_ref_no") <> "" Then 'get from fa taping
conn3("select * from fa_taping where fa_ref_no='" & dr1("fa_ref_no") & "' and revision='" & dr1("revision") & "'", "taping")
If ds2.Tables("taping").Rows.Count > 0 Then 'fa taping record found
dr2 = ds2.Tables("taping").Rows(0)
qty = dr2("qty_per_reel")
If CInt(txtQty.Text) > qty Then 'more than 1 reel
part = CInt(txtQty.Text) Mod qty
reel = (CInt(txtQty.Text) - part) / qty
For j As Integer = 0 To reel - 1
insert(CStr(qty))
Next
If part <> 0 Then
insert(CStr(part))
End If
Else
insert(txtQty.Text)
End If
Else 'no fa taping record found, use fa taping mast
conn4("select * from fa_taping_mast where pkg='" & dr1("pkg") & "' and lead='" & dr1("lead") & "' and status='Approved'", "mast")
If ds3.Tables("mast").Rows.Count > 0 Then 'fa taping mast record found
dr3 = ds3.Tables("mast").Rows(0)
qty = dr3("qty_per_reel")
If CInt(txtQty.Text) > qty Then 'more than 1 reel
part = CInt(txtQty.Text) Mod qty
reel = (CInt(txtQty.Text) - part) / qty
For k As Integer = 0 To reel - 1
insert(CStr(qty))
Next
If part <> 0 Then
insert(CStr(part))
End If
Else
insert(txtQty.Text)
End If
Else 'no fa taping mast record found
insert(txtQty.Text)
End If
End If
Else 'get from fa taping mast
conn3("select * from fa_taping_mast where pkg='" & dr1("pkg") & "' and lead='" & dr1("lead") & "' and status='Approved'", "taping_mast")
If ds2.Tables("taping_mast").Rows.Count > 0 Then 'fa taping mast record found
dr2 = ds2.Tables("taping_mast").Rows(0)
qty = dr2("qty_per_reel")
If CInt(txtQty.Text) > qty Then 'more than 1 reel
part = CInt(txtQty.Text) Mod qty
reel = (CInt(txtQty.Text) - part) / qty
For l As Integer = 0 To reel - 1
insert(CStr(qty))
Next
If part <> 0 Then
insert(CStr(part))
End If
Else '1 reel
insert(txtQty.Text)
End If
Else 'no fa taping mast record found
insert(txtQty.Text)
End If
End If
End If
printing()
clear()
txtJob.Text = ""
txtJob.Focus()
End Sub
Private Sub btnPaper_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnPaper.Click
Dim p As Form
p = Celclass_papertaping
Me.Close()
p.Show()
End Sub
结束Class
错误
Private Sub txtJob_TextChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles txtJob.TextChanged conn1("select p.qty, p.lot, p.mpn, p.dc1, p.dc2, p.dc3, s.raw, s.so_raw, s.prog, s.po, p.job_no from prod_pt p inner join pln_so s on p.so_id=s.so_id where p.job_no='" & txtJob.Text & "'", "pt")
精简到最简单的级别，您将得到一个 WhosebugException，因为您正在其自己的 TextChanged 事件处理程序中更改 txtJob.Text。所以最终发生的是：
- 用户在
txtJob中输入了一些内容。 - 引发了
txtJob.TextChanged事件。 - 您的
txtJob_TextChanged事件处理程序被调用。 - 在
txtJob_TextChanged内，您的代码更改txtJob.Text。 - 引发了
txtJob.TextChanged事件。 - 重复3-6直到堆栈溢出。
解决方法是添加一个 Boolean 标志，指示代码仍在处理文本更改：
Private _istxtJobProcessing As Boolean
Private Sub txtJob_TextChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles txtJob.TextChanged
'If we're already processing, bail out now.
If _istxtJobProcessing Then Return
'Set a flag so that we know that we are already processing.
_istxtjobProcessing = True
' Now run your code here...
' And afterward, reset the flag.
_istxtJobProcessing = False
End Sub
您还应注意，您正在编写的 SQL 代码容易受到 SQL injection 的攻击。如果您搜索该主题，您会在 VB.NET.
中找到大量关于如何使用参数化查询避免这种情况的答案