int current = this.listView1.SelectedIndices[0];
int next = current == this.listView1.Items.Count - 1 ? 0 : current + 1;
this.listView1.Focus();
this.listView1.Items[next].Selected = true;
this.listView1.Items[current].Selected = false;

note: this will jump back to the first one when the last one was selected

Comments
Thanks, very helpful
int current = this.listView1.SelectedIndices[0];
int next = current == this.listView1.Items.Count - 1 ? 0 : current + 1;
this.listView1.Focus();
this.listView1.Items[next].Selected = true;
this.listView1.Items[current].Selected = false;

note: this will jump back to the first one when the last one was selected

thanks that worked. And to make it go the other way is a very simple tweak :)
Thanks again

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