Late but in case anyone still googles for the solution:
You can create a new line Feature Class, edit it, select and copy the polygons and paste them to the line FC. If you want to keep some attributes, you should create the attributes (same type and name) in the line FC first.
サインインしたメンバーは投稿、更新のフォローなどができます。初めてですか?無料アカウントを登録してください。
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