c# - Code For Random not working properly -

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• random number generator generating 1 random number 9 answers

i creating random function give me 4 random values of a,b,c,d , sign(+,-). problem code generates same values , output has a=b=c=d=x x random value generated code. tried put breakpoint , debug it, works fine no problems remove break point same issue occurs. can please tell me going wrong. code follows:

public void randomquestiongenerate()     {//all variables(a,b,c,d,sign1,sign2) globally defined         random firstno = new random();         = firstno.next(0, 10);         random secondno = new random();         texta.text = a.tostring();          b = secondno.next(0, 10);         random thirdno = new random();         textb.text = b.tostring();          c = thirdno.next(0, 10);         random fourthno = new random();         textc.text = c.tostring();          d = fourthno.next(0, 10);         textd.text = d.tostring();          random firstsign = new random();         int x = firstsign.next(0, 2);         if(x == 0)         {             sign1 = "+";         }         else if(x == 1)         {             sign1 = "-";          }         textsign1.text = sign1;           random secondsign = new random();         int y = secondsign.next(0, 2);         if (y == 0)         {             sign2 = "+";         }         else if (y == 1)         {             sign2 = "-";         }         textsign2.text = sign2;     } 

you should have one instance of random, preferably entire program.

random automatically seeded time-based value when create using default constructor:

initializes new instance of random class, using time-dependent default seed value.

https://msdn.microsoft.com/en-us/library/h343ddh9(v=vs.110).aspx

the problem is, creating 4 instances faster resolution of time-based value. 4 instances being seeded same value. , when called same parameters, each return same value.

because of race conditions this, should keep 1 global instance of random if possible.