C#

public class IDGenerator
{
    int min, max;

    Random r = new Random(unchecked((int)DateTime.Now.Ticks));

    public IDGenerator ()
    {
        this.min = 1000000;
        this.max = 9999999;
    }

    public string GetID ()
    {
        // Produce a number from min through max.
        // Use the RNG created at the class level.
        String myNumber = r.Next(min,max).ToString("0000000");
        return myNumber;
    }
}

int min = 1000000, max = 9999999;
Random r = new Random();
for(int i = 0; i < 5; i++)
{
    Console.WriteLine(r.Next(min, max));
}

1. The second parameter is ignored if the Filename refers to a local file (on the hard disk), and
2. CopyFile is a variant of type VT_BOOL (bool), so even if you had to specify it (i.e., Filename refers to a file on a network share, for example) you need to cast it to an object which gets marshaled as a VARIANT (native type):

   object copyFile = true;
   excelApp.AddIns.Add("filename", copyFile);

   You don't need to specify the second parameter, however, if you always know the file will be on hard disk. If you know this assumption is safe, then use object copyFile = Missing.Value; instead of assigning a bool.
   
   This posting is provided "AS IS" with no warranties, and confers no rights.
   
   Software Design Engineer
   Developer Division Sustained Engineering
   Microsoft
   
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