C# 高级HMI订阅具有指向m_SynchronizingObject的空指针
我尝试订阅时出错。m_Plc.Read函数工作正常,但对于我的应用程序来说速度太慢 这是我的代码:C# 高级HMI订阅具有指向m_SynchronizingObject的空指针,c#,wpf,C#,Wpf,我尝试订阅时出错。m_Plc.Read函数工作正常,但对于我的应用程序来说速度太慢 这是我的代码: private AdvancedHMIDrivers.EthernetIPforCLXCom m_Plc; public MainPageViewModel() { m_Plc = new EthernetIPforCLXCom(); m_Plc.IPAddress = m_IPAddress; m_Plc.ProcessorSlot = Convert.ToInt32(m_Pr
private AdvancedHMIDrivers.EthernetIPforCLXCom m_Plc;
public MainPageViewModel()
{
m_Plc = new EthernetIPforCLXCom();
m_Plc.IPAddress = m_IPAddress;
m_Plc.ProcessorSlot = Convert.ToInt32(m_ProcessorSlot);
m_Plc.ComError += DoOnCommError;
m_Plc.SubscriptionError += DoOnCommError;
string testString = m_Plc.Read("MyTag");
int index = m_Plc.Subscribe("MyTag", 1, 2000, testPlcReaded);
}
private void testPlcReaded(object sender, MfgControl.AdvancedHMI.Drivers.Common.PlcComEventArgs e)
{
try
{
Console.WriteLine(e.Values[0]);
}
catch (Exception ex)
{
Console.WriteLine(ex);
}
}
这就是我得到的错误:
m_SynchronizingObject.BeginInvoke(SubscriptionList(i).dlgCallBack,z)
位于以下文件夹中:EthernetIPforCLXCom.vb
存在指向m_SynchronizingObject的空指针
错误详细信息:
System.NullReferenceException was unhandled by user code
HResult=-2147467261
Message=Object reference not set to an instance of an object.
Source=AdvancedHMIDrivers
StackTrace:
at AdvancedHMIDrivers.EthernetIPforCLXCom.DataLinkLayer_DataReceived(Object sender, PlcComEventArgs e) in C:\prj\TLLAB\TLLAB\AdvancedHMIBeta363 (1)\AdvancedHMIDrivers\EthernetIPforCLXCom.vb:line 1269
at MfgControl.AdvancedHMI.Drivers.CIP.OnDataReceived(PlcComEventArgs e)
at MfgControl.AdvancedHMI.Drivers.CIP.DataReceivedEIP(Object sender, PlcComEventArgs e)
您没有实例化您的对象。当您尝试使用它时,它是空的。 这将有助于:
private EthernetIPforCLXCom m_Plc = new EthernetIPforCLXCom
{
IPAddress = m_IPAddress,
ProcessorSlot = Convert.ToInt32(m_ProcessorSlot),
ComError += DoOnCommError,
SubscriptionError += DoOnCommError
};
在当前版本中对我来说似乎是个bug 代码检查SynchronizingObject是否为null,或者在调用它之前是否创建了它的句柄,所以如果它为null,它就会崩溃
If m_SynchronizingObject Is Nothing OrElse DirectCast(m_SynchronizingObject, Windows.Forms.Control).IsHandleCreated Then
'...<some code>...
m_SynchronizingObject.BeginInvoke(SubscriptionList(i).dlgCallBack, z)
End If
如果m_synchroningobject为Nothing或lse DirectCast(m_synchroningobject,Windows.Forms.Control)。则会创建IShandle
'......
m_SynchronizingObject.BeginInvoke(SubscriptionList(i).dlgCallBack,z)
如果结束
您应该提交一个bug,因为它可能是这样的
If m_SynchronizingObject IsNot Nothing AndAlso DirectCast(m_SynchronizingObject, Windows.Forms.Control).IsHandleCreated Then
'...<some code>...
m_SynchronizingObject.BeginInvoke(SubscriptionList(i).dlgCallBack, z)
Else
'...<some other code>...
End If
如果m_SynchronizingObject不是空的,也不是DirectCast(m_SynchronizingObject,Windows.Forms.Control)。则是创建的
'......
m_SynchronizingObject.BeginInvoke(SubscriptionList(i).dlgCallBack,z)
其他的
'......
如果结束
编辑:我将此发布到,Archie已经解决了下一版本的问题您可能应该实例化您的对象,例如:private AdvancedHMIDrivers.EthernetIPforCLXCom m_Plc=new EthernetIPforCLXCom();感谢您的快速响应!我从VisualStudio中复制错了,我自己已经改变了。所以我还是有同样的错误(m_IPAddress和m_ProcessorSlot是否实例化?是的,它们已定义并实例化。plc.Read()工作正常,因此plc实例化良好。