If you find yourself in this situation, then you’ll have to solve the problem in code.
Although asynchronous events expose a SPItem Event Properties parameter named properties just like their synchronous counterparts, remember that the operation has already completed so you cannot modify anything in the properties parameter (well, you can, but it doesn’t do anything).
Additionally, the properties parameter may not be populated with information that you would tend to expect to be present.
This walkthrough is based on the first one where I have a custom list with planets of our solar system.
Users can change data like the number of moons or the distance to the earth, but they are not able to change the name of the planet.
If you wish to modify a property value on the list item during the event, the value should be updated in After Properties property of the properties parameter.
Share Point reads these values from the event parameter and modifies the item accordingly when the actual operation runs (e.g.You just have to check to see if the vti_sourcecontrolcheckedoutby property on the item was cleared: will not. You can also use event receivers to validate the data that the user wants to change.One major thing you should know about the SPItem Event Receiver class is that while you can implement multiple list item event handlers in a single class, Share Point instantiates a new instance of that class for each individual event it needs to handle.What this means is that you cannot store data in instance-level variables and share that data between event handlers.To check if the name of the planet is changed, you can compare the Title column before the changes with the Title of the changed item.