省份与城市的二级级联 用javascript实现答:150429|宁城县,150430|敖汉旗,150500|通辽市,150501|市辖区,150502|科尔沁区,150521|科尔沁左翼中旗,150522|科尔沁左翼后旗,150523|开鲁县,150524|库伦旗,150525|奈曼旗,150526|扎鲁特旗,150581|霍林郭勒市,150600|鄂尔多斯市,150601|市辖区,150602|东胜区,150621|达拉特旗,150622|准格尔旗,150623|鄂托克前旗,150624|...