This sample demonstrates how to call a Fortran DLL from Visual BASIC.NET and how to pass simple arguments.
.sln file"VBCallsFortran" " is not shown in boldface type in the Solution Explorer,
right-click on project ""VBCallsFortran" " and select "Set as StartUp Project".
Build > Clean SolutionBuild > Build SolutionDebug > Start Without Debugging or press Ctrl-F5
A "Do It" button will be displayed along with four input values. Click the button. The VB code will call the Fortran routine DLL_ROUT and pass it a double precision real input array, a string, and a double-precision output array. The Fortran code uses an internal READ to convert the string to a number, multiplies it by the values in the input array, and then stores the result in the output array.
build.bat cleanbuild.bat releasebuild.bat debugVBCallsFortran in Visual Studio IDEFcall.dll built from above steps under directory .\debug or .\release to the VB project output folder VBCallsFortran\bin\Debug or VBCallsFortran\bin\ReleaseVBCallsFortran\bin\Debug\VBCallsFortran.exe or VBCallsFortran\bin\Release\VBCallsFortran.exe from the command window"VBCallsFortran" and choose Properties. In the left column, select
"Debug" > tab and check the box labeled "Enable native code debugging", close the properties page to save the changes.
Form1.vb and double-click on the Push Me button.