Uncaught TypeError: this.props.books.forEach is not a function var BookTable = React.createClass({ render: function() { var rows = []; this.props.books.forEach(function(book) { // ← ここでエラー rows.push(<BookTableRow key={book.id} book={book} handleEditClickPanel={this.props.handleEditClickPanel} />); }…</booktablerow>