Two-wheeler lock having an alarm function

A lock having an alarm function for a two-wheeler, comprising a lock body and a securing hoop that is movable relative to the lock body between a securing position to secure the two-wheeler and an open position to release the two-wheeler, wherein the lock body has a locking mechanism to selectively lock the securing hoop at the lock body in the securing position, and wherein the lock body furthermore comprises an alarm device for outputting an alarm signal, wherein the locking mechanism can selectively be moved into an unlocked position, a locked position, or an alarm activation position, with the securing hoop being released for a movement into the open position in the unlocked position, with the securing hoop located in the securing position being locked at the lock body in the locked position, and with the alarm device being activated or being able to be activated by moving the locking mechanism into the alarm activation position, wherein the alarm activation position forms a further locked position, wherein the alarm device is deactivated in the locked position, and wherein in the further locked position the securing hoop located in the securing position is locked at the lock body and the alarm device is activated, wherein the locking mechanism has two latches, wherein the securing hoop has a first hoop end and a second hoop end, of which each has a first locking recess and a second locking recess, wherein in the locked position of the locking mechanism one of the two latches engages into the first locking recess of the first hoop end and the other one of the two latches engages into the first locking recess of the second hoop end, and wherein in the further locked position of the locking mechanism the one of the two latches engages into the second locking recess of the second hoop end and the other one of the two latches engages into the second locking recess of the first hoop end.