AggregateException C# example

Question

I have seen an example of AggregateException on the web and I\'m trying to figure out how it works. I have written a simple example, but my code for some reason

Answer 1

AggregateException is often used for catching exceptions, that might occur when waiting for a Task to complete. Because Task in general can consist of multiple others, we do not know, whether there will be one or more exceptions thrown.

Check the following example:

// set up your task
Action job = (int i) =>
{
    if (i % 100 == 0)
        throw new TimeoutException("i = " + i);
};

// we want many tasks to run in paralell
var tasks = new Task[1000];
for (var i = 0; i < 1000; i++)
{
    // assign to other variable,
    // or it will use the same number for every task
    var j = i; 
    // run your task
    var task = Task.Run(() => job(j));
    // save it
    tasks[i] = task;
}

try
{
    // wait for all the tasks to finish in a blocking manner
    Task.WaitAll(tasks);

}
catch (AggregateException e)
{
    // catch whatever was thrown
    foreach (Exception ex in e.InnerExceptions)
        Console.WriteLine(ex.Message);
}