Current scene number

Could anybody please show me how to get the current scene number? Actually, I want to code like this “Current Level Number + 1”. (whenever player finished, he would go to next level automatically).

With Application.loadedLevel now obsolete in Unity 5 use

SceneManager.GetActiveScene().buildIndex

Returns the index of the scene in the Build Settings. Always returns -1 if the scene was loaded through an AssetBundle.

http://unity3d.com/support/documentation/ScriptReference/Application-loadedLevel.html