我有一个应用程序调用一个方法，通过SQL对AS400进行一些查询调用。长话短说我启动了一个线程并将此方法放入此线程中。但其余按钮没有响应我需要应用程序在此循环完成时响应。例如，如果用户需要关闭应用程序，我需要关闭打开的线程并关闭应用程序。我该怎么做呢？我读了一些关于创建另一个UI功能的线程，但它不起作用。我该如何设置？
Imports Microsoft.VisualBasic
Imports System.Threading
Public Class frmAbsenceTracking
Public Sub ScheduledToday()
Dim yr, wk, dy, i As Integer
Dim dbconn As New WES.Core.Database.SQLConnection
Dim Empdbconn As New WES.Core.Database.SQLConnection
Dim sql, empSQL As String
Dim ds As DataSet
Dim empds As DataSet
dbconn("@DTDDWD") = DateAdd("d", -1, Now).Day
dbconn("@DTMMWD") = DateAdd("d", -1, Now).Month
dbconn("@DTCCWD") = ((DateAdd("d", -1, Now).Year).ToString).Substring(0, 2)
dbconn("@DTYYWD") = ((DateAdd("d", -1, Now).Year).ToString).Substring(2)
sql = "SELECT yearwd, wk#wd, day#wd From ISERIES.WES.WQDATA.PRWKDAPF WHERE DTDDWD = @DTDDWD AND DTMMWD = @DTMMWD AND DTYYWD = @DTYYWD AND DTCCWD = @DTCCWD"
ds = dbconn.FillDataSet(sql)
yr = ds.Tables(0).Rows(0)("yearwd")
wk = ds.Tables(0).Rows(0)("wk#wd")
dy = ds.Tables(0).Rows(0)("day#wd")
Empdbconn("@year") = yr
Empdbconn("@week") = wk
Empdbconn("@day") = dy
empSQL = "SELECT emp#sd FROM ISERIES.WES.WQDATA.PRSDTll9 WHERE yearsd = @year and wk#sd = @week and day#sd = @day"
empds = Empdbconn.FillDataSet(empSQL)
Dim Employee(empds.Tables(0).Rows.Count) As Integer
If Label2.InvokeRequired Then
Label2.BeginInvoke(New ScheduledTodayDelegate(AddressOf ScheduledToday))
Else
Label2.Text = "Last Scan Started: " + Now
Label2.Refresh()
End If
Dim Absentees(empds.Tables(0).Rows.Count) As Integer
'may throw out of bounds for i
For i = 0 To empds.Tables(0).Rows.Count - 1
Employee(i) = CInt(empds.Tables(0).Rows(i)("emp#sd"))
If EmpList.InvokeRequired Then
EmpList.BeginInvoke(New ScheduledTodayDelegate(AddressOf ScheduledToday))
Else
EmpList.Items.Add("Scannning Employee:" + Employee(i).ToString)
EmpList.Refresh()
End If
If hasAbsences((Employee(i)), yr, wk, dy) = True Then
Absentees(i) = Employee(i)
' BuildReport(Absentees(i))
End If
Next
Label1.Text = "Last Completed Scan: " + Now
If EmpList.Items.Count > 10000 Then
EmpList.Items.Clear()
End If
End Sub
Public Sub BuildReport(Employee As Integer)
End Sub
Private Delegate Sub ScheduledTodayDelegate()
Private Delegate Function exitAppDelegate()
Public Function hasAbsences(empNumber As Integer, yr As Integer, wk As Integer, dy As Integer) As Boolean
Dim dbconn As New WES.Core.Database.SQLConnection
Dim dbconn2 As New WES.Core.Database.SQLConnection
Dim sql, sql2 As String
Dim ds, ds2 As DataSet
Dim Parts = Split(Now.ToShortDateString, "/")
dbconn("@Employee") = empNumber
dbconn("@year") = yr
dbconn("@week") = wk
dbconn("@day") = dy
' Dim ReturnDataStuff = returnDateStuff(yr, wk, dy)
' Dim Assemble = AssembleDate(CInt(Parts(2).Substring(0, 2)), CInt(Parts(2).Substring(2)), CInt(Parts(0)), CInt(Parts(1)))
sql = "SELECT yearsd, wk#sd, day#sd FROM ISERIES.WES.WQDATA.PRSDTll7 WHERE (emp#sd = @Employee AND yearsd < @year) OR (emp#sd = @Employee AND yearsd = @year AND wk#sd < @week) OR (emp#sd = @Employee AND yearsd = @year AND wk#sd = @week AND day#sd < @day) ORDER BY yearsd asc, wk#sd asc, day#sd asc"
ds = dbconn.FillDataSet(sql)
dbconn2("@Employee") = empNumber
dbconn2("@StartDate") = returnDateStuff(ds.Tables(0).Rows(ds.Tables(0).Rows.Count - 2)("yearsd"), ds.Tables(0).Rows(ds.Tables(0).Rows.Count - 2)("wk#sd"), ds.Tables(0).Rows(ds.Tables(0).Rows.Count - 2)("day#sd"))
dbconn2("endDate") = AssembleDate(CInt(Parts(2).Substring(0, 2)), CInt(Parts(2).Substring(2)), CInt(Parts(0)), CInt(Parts(1)))
sql2 = "SELECT * FROM ISERIES.WES.WQDATA.PRWKPNl7 WHERE emp#wp = @Employee and pdatwp > @StartDate AND pdatwp < @endDate"
ds2 = dbconn2.FillDataSet(sql2)
If ds2.Tables(0).Rows.Count <= 0 Then
If EmpList.InvokeRequired Then
EmpList.BeginInvoke(New ScheduledTodayDelegate(AddressOf ScheduledToday))
Else
EmpList.Items.Add(empNumber.ToString + "out for 2 or more days")
EmpList.Refresh()
End If
Return True
Else
Return False
End If
End Function
Public Function returnDateStuff(yr As Integer, wk As Integer, dy As Integer) As Long
Dim ccx, yyx, mmx, ddx As Integer
Dim ds As DataSet
Dim sql As String
Dim dbconn As New WES.Core.Database.SQLConnection
dbconn("@year") = yr
dbconn("@week") = wk
dbconn("@day") = dy
sql = "SELECT DTDDWD, DTMMWD, DTYYWD, DTCCWD FROM ISERIES.WES.WQDATA.PRWKDAPF WHERE yearwd = @year AND wk#wd = @week AND day#wd = @day"
ds = dbconn.FillDataSet(sql)
ddx = ds.Tables(0).Rows(0)("DTDDWD")
mmx = ds.Tables(0).Rows(0)("DTMMWD")
yyx = ds.Tables(0).Rows(0)("DTYYWD")
ccx = ds.Tables(0).Rows(0)("DTCCWD")
Return AssembleDate(ccx, yyx, mmx, ddx)
End Function
Public Function AssembleDate(cc As Integer, yy As Integer, mm As Integer, dd As Integer) As Long
Dim t, tc, ty, tm, td As String
tc = CStr(cc)
ty = CStr(yy)
tm = CStr(mm)
td = CStr(dd)
If Len(ty) = 1 Then
ty = "0" & ty
End If
If Len(tm) = 1 Then
tm = "0" & tm
End If
If Len(td) = 1 Then
td = "0" & td
End If
t = tc + ty + tm + td
Return CLng(t)
End Function
Private Sub exitApp()
If ExitBtn.InvokeRequired Then
ExitBtn.BeginInvoke(New ScheduledTodayDelegate(AddressOf exitApp))
Else
Application.Exit()
End If
End Sub
Private Sub ForceBtn_Click(sender As Object, e As EventArgs) Handles ForceBtn.Click
Dim t1 As System.Threading.Thread = New System.Threading.Thread(AddressOf Me.ScheduledToday)
t1.Start()
'ScheduledToday()
End Sub
Private Sub ExitBtn_Click(sender As Object, e As EventArgs) Handles ExitBtn.Click
Dim t2 As System.Threading.Thread = New System.Threading.Thread(AddressOf Me.exitApp)
t2.Start()
End Sub
End Class
答案 0 :(得分：0)
你可以使用像这样的任务......
Imports System.Threading.Tasks
...
Dim t = Task.Factory.StartNew(Function()
Return SomeFunctionYouWantToCallInTheBackground()
End Function)
要在该函数内执行任何UI更新，请使用Invoke或BeginInvoke调用另一个将更新UI的函数。 Invoke和BeginInvoke强制调用在UI线程中发生。
如果您需要等待任务结束，请使用：
Dim result = t.Result
如果你的后台任务没有返回值，你可以使用Sub而不是像这样的函数：
Dim t = Task.Factory.StartNew(Sub()
SomeFunctionYouWantToCallInTheBackground()
End Sub)
并使用t.Wait（）等待它完成，因为没有结果。
有关详情，请访问Google“System.Threading.Tasks.Task”