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/**
 * Gravity Wiz // Gravity Forms // Populate Field from One Page to Field in Subsequent Page
 * http://gravitywiz.com/
 */

// update "1074" to the ID of your form
add_filter( 'gform_pre_render_1074', function( $form ) {

	foreach( $form['fields'] as &$field ) {
		// update "2" to the field ID on the later page
		if( $field->id == 2 ) {
			// update "1" to the field ID on the earlier page
			$field->defaultValue = rgpost( 'input_1' );
		}
	}

	return $form;
} );