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Handler itemupdating

handler itemupdating-23

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.

It’s very easy to spot if a function is synchronous or asynchronous based on its name. Before Properties[«Field Name »] And yes, three possibilities depending on the actions and the synchronicity of the eventcan contain either the new value, or the old value, or nothing at all!Previously I worked as a Premier Field Engineer for Share Point @ Microsoft Belgium.For 5 successive years I’ve been rewarded as Share Point Server MVP for my contribution to the Share Point community: I developed the U2U CAML Query Builder and its successor the CAML Designer, which I develop together with Andy Van Steenbergen.For this we must add the synchronization parameter to our xml definition.Developing a Sharepoint application would have all the fun of a video game, if only you had infinite lives.To avoid this error, we can define the event “Item Added” as synchronous!

Indeed, all asynchronous event can be defined as synchronous!

The changed values can be retrieved from the After Properties of the incoming properties argument.

You could think that the current values are stored in the Before Properties of the item but that’s not true: the Before Properties are unreliable at this point. When the name of the planet is changed, the update is canceled and an error message is returned to the user.

This event occurs before the data is saved to the Share Point list.

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.

For the lists Those informations are very important to consider when planning a development.