Writes a
System.Double value into a named OPC item. A corresponding data type is passed to the OPC server.
Syntax
'Declaration
<ExtensionAttribute()>
Public Overloads Shared Sub WriteItemValueDouble( _
ByVal As IEasyDAClient, _
ByVal As String, _
ByVal As String, _
ByVal As String, _
ByVal As Double _
)
'Usage
Dim client As IEasyDAClient
Dim machineName As String
Dim serverClass As String
Dim itemId As String
Dim value As Double
IEasyDAClientExtension2.WriteItemValueDouble(client, machineName, serverClass, itemId, value)
[Extension()]
public static void WriteItemValueDouble(
IEasyDAClient ,
string ,
string ,
string ,
double
)
[Extension()]
public:
static void WriteItemValueDouble(
IEasyDAClient^ ,
String^ ,
String^ ,
String^ ,
double
)
Parameters
- client
- The client object that will perform the operation.
- machineName
- Name of the machine. Determines the computer on which the OPC server is located. It may be an empty string, in which case the OPC server is assumed to exist on the local computer or at the computer specified for it by DCOM configuration.
- serverClass
- Contains ProgID of the OPC server to read from.
- itemId
- Contains OPC item identifier.
- value
- The value to be written.
Exceptions
| Exception | Description |
|---|
| System.ArgumentNullException |
A null reference (Nothing in Visual Basic) is passed to a method that does not accept it as a valid argument.
This is a usage error, i.e. it will never occur (the exception will not be thrown) in a correctly written program. Your code should not catch this exception. |
| OpcLabs.EasyOpc.OperationModel.OpcException |
The OPC "Classic" (or OPC XML-DA) operation has failed. This operation exception in uniformly used to allow
common handling of various kinds of errors. The System.Exception.InnerException always contains
information about the actual error cause.
This is an operation error that depends on factors external to your program, and thus cannot be always avoided. Your code must handle it appropriately. |
Requirements
Target Platforms: .NET Framework: Windows 10 (selected versions), Windows 11 (selected versions), Windows Server 2016, Windows Server 2022; .NET: Linux, macOS, Microsoft Windows
See Also
