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Question

I'm trying to use 4 progress bars in a 4 step process. Essentially the progress bars are being used because the project takes a LONG time to run, using a single progress bar with the (divide by ten) that normally is used would mean that the progress bar would gain 1 sliver every 20 minutes. (too long.)

Here is the code:

backgroundWorker1.ReportProgress(a++);

if (a == 100)
{
    backgroundWorker2.ReportProgress(b++);
    a = 0;
}

if (b == 100)
{
    backgroundWorker3.ReportProgress(c++);
    b = 0;
}

if (c == 100)
{
    c = 0;
    d = 25;
}

backgroundWorker4.ReportProgress(d);

The problem is, the first progress bar goes to about 99% and stops, the 2nd bar doesn't move at all but the process is still running.

Answer 1

Try to do parameter increment before passing to method. In C# increment operator can appear before and after its operand. When you do (a++) it is postfix increment operation. Result of this operation is value of a before it was incremented. Thus maximum value passed to ReportProgess will be 99 instead of 100. If you change increment operation to (++a), which is prefix increment, then result of operation will be value of a after increment:

backgroundWorker1.ReportProgress(++a);

Same with other calls. Btw last reporting is strange - value of d changed only once. Maybe you should use d += 25 instead?