Generate interface with VC ++ COleDispatchDriver wrapper class to call the COM component

In general, you can use CoCreateInstance to invoke the COM component. But for the COM component implements IDispatch interface, there are easier ways - automatically generated interface with VC ++ COleDispatchDriver wrapper class to call the COM component.

 

For example: execute scripts statement in VC ++, such as VBScript statement.

 

The system provides a control: C: \ WINDOWS \ system32 \ msscript.ocx, which provides an interface called IScriptControl through it, we can execute the script statements.

 

1. VC ++ wrapper classes created automatically

MFC with VC support the establishment of a project, add a class, select the "type of MFC class library," and then select msscript.ocx file and IScriptControl added to the right column, as shown ++: can be generated after clicking the completion CScriptControl packaging .


 

 

2. using the generated class

    // initialize the COM library

    CoInitialize(NULL);

 

    // create MSScriptControl.ScriptControl instance

    // The name (ProgId) by VC ++ gadget directory oleview get.

    CScriptControl js;

    if (js.CreateDispatch("MSScriptControl.ScriptControl"))

    {

        // set the current scripting language used

        js.put_Language("JScript");

        // execute a statement , after the completion of the implementation of var ie it contains the result of the expression

        VARIANT var=js.Eval("1.234+5.31");

        // release Interface

        js.ReleaseDispatch();

    }

       

    // close the COM library

    CoUninitialize();

 

 3. The other use of this embodiment

can be conveniently packaged as a dot code these expression evaluator.

Reproduced in: https: //www.cnblogs.com/rogee/archive/2011/02/19/1958690.html