/// <summary>
/// Dispose implementation, checking post conditions for purpose and saving.
/// </summary>
/// <param name="disposing">Are we disposing?</param>
protected virtual void Dispose(bool disposing)
{
if (disposing)
{
// We're disposing and SaveChanges wasn't called. That usually
// means we're exiting the scope with an exception. Block saves
// of the entire unit of work.
if (this.purpose == DbContextScopePurpose.Writing && !this.saveChangesCalled)
{
this.scopedDbContexts.BlockSave = true;
// Don't throw here - it would mask original exception when exiting
// a using block.
}
if (this.scopedDbContexts != null && this.isRoot)
{
this.scopedDbContexts.Dispose();
this.scopedDbContexts = null;
}
}
}
/// <summary>
/// Initializes a new instance of the <see cref="DbContextScope" /> class.
/// </summary>
/// <param name="purpose">Will this dbcontext scope be used for reading or writing?</param>
/// <param name="isNewScope">Will this dbcontext scope be a new DbContextScope.</param>
public DbContextScope(DbContextScopePurpose purpose, bool isNewScope = false)
{
this.purpose = purpose;
this.parentScope = GetAmbientScope();
if (this.parentScope != null && !isNewScope)
{
this.scopedDbContexts = this.parentScope.DbContext;
}
else
{
this.scopedDbContexts = new DbContextCollection(purpose == DbContextScopePurpose.Writing);
this.isRoot = true;
}
this.SetAmbientScope(this);
if (purpose == DbContextScopePurpose.Writing && !this.scopedDbContexts.ForWriting)
{
throw new InvalidOperationException(
"Can't open a child DbContextScope for writing when the root scope " +
"is opened for reading.");
}
}