Threads have same parameters

Question

I call with threads recursive function. But not work, because all threads have same parameters: problem is i. All i=st. Later all recursive function not working ok.

threads = new Thread[st];
for (int i = 1; i <= st; i++)
 {
 Thread t1 = new Thread(() =>
 {
 rek_md5(crke, i, new char[i], 0, md5Hash);
 });
 t1.Name = i.ToString();
 threads[i-1] = t1;
 t1.Start();
 }

How can I fix, all threads have different parameters.

In fact it is not dublicate, it is a copy of http://stackoverflow.com/questions/28031168/threads-not-make-program-faster — I4V, Jan 20 '15 at 22:18

adv12 · Answer 1 · 2015-01-19T20:00:23.143

0

This is because the lambda makes a closure over i, such that the code inside the lambda always sees the value of i that ended the for loop, because that's the value of i by the time the lambda runs. Here's some more info:

http://blogs.msdn.com/b/ericlippert/archive/2009/11/12/closing-over-the-loop-variable-considered-harmful.aspx

edited Jan 19 '15 at 20:00

answered Jan 19 '15 at 19:32

adv12

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Threads have same parameters

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