Question

I have an asp.net page that execute some update to db. The updates takes 2-3 seconds, all these hapends in a method that first read data from db and do some updates. When the page request are less then 2 sec for these action, the db read code, read the same state of records in db, and all update actions of asp.net page requests updates the same records.

How i can prevent these, that the newest request wait untill the oldest finish their execution?

Any ideas?

Answer 1

If I’m understanding you correctly, you want to block access to a particular set of methods until the process has been completed.

Easy enough… create a static method and implement a lock(). You can get real fancy with share locks, upgrades to read/write locks, etc… but the basic principal is that you lock your critical sections of shared code so other users cannot enter those sections.

http://msdn.microsoft.com/en-us/library/c5kehkcz(v=vs.71).aspx

The lock keyword marks a statement block as a critical section by obtaining the mutual-exclusion lock for a given object, executing a statement, and then releasing the lock.

static object lockObject = new Object();
static bool inProgress = false;

static void MyProcess()
{
  if(inProgress) return;

  lock(lockObject)
  {
    try{
      inProgress = true;
      // critical code here
    }
    finally
    {
      inProgress = false;
    }
  }
}