问题
Raleted to:
Lock in static methods
lock Statement
please consider this code:
public static class SomeClass
{
public static void Method1(string key, int item)
{
//Some Work
}
public static DataTable Method2()
{
//Some Work
}
....
If I want to use this class in Asp.Net application from performance point of view does it need separate lock object for every methods like this:
public static class SomeClass
{
private Object thisLock1 = new Object();
public static void Method1(string key, int item)
{
lock(thisLock1)
{
//Some Work
}
}
private Object thisLock2 = new Object();
public static DataTable Method2()
{
lock(thisLock2)
{
//Some Work
}
}
....
回答1:
You don't HAVE to lock the object when you try to access it, but it's highly recommended.
If you don't want to perform these locks yourself, Microsoft added a class that's thread safe, it's the ConcurrentBag Class, it's great because this logic is already implemented, so you can access and remove it from several threads or classes.
However, locks give you a finer control over list access. Check this link for examples of bag implementation.
回答2:
Is lock object deparatly necessary for every static methods
NO, and NO
consider this case
You have another method called RemoveFromCache and it uses lock3
lock3 on thread 1
ItemRemove Iteration Start
lock1 on thread 2
Item Removed
thread1 Iterator.Next
Exception on thread1 due to collection modified. Anyone can get an instance of the collection with GetAllItems method. It is hard to enforce thread safety with your private lock. You should consider using one of those thread safe collection instead.
来源：https://stackoverflow.com/questions/47944037/is-lock-object-deparatly-necessary-for-every-static-methods