Public Bool Get Set Statement

Question

无论如何，这个语句应该有效，但是当我编译时会返回错误？想法？

public bool sheetCreatorSave {
    get {
        return (bool)this["sheetCreatorSave"];
    }
    set {
        this["sheetCreatorSave"] = (object)(bool)(value ? 1 : 0);
    }
}