select下拉框内容回显 并将对应的option设置为selected选中状态

<script type="text/javascript">

    var productId = '${product.productId}';

    _findSelectedData();

    function _findSelectedData(){
        jQuery.ajax({
            dataType: "json",
            url: "/product/getProductById",
            data: {productId:productId},
            type: "POST",
            success: function (result) {
                if (result.code == 1) {

                  var data = result.data;

                  var productType = data.productType;//经验大类
                    var isAProduct = data.isAProduct;//是否短期活动

                    //方法1
                   $('#productType').find('option[value='+productType+']').attr('selected','selected');
                   $('#isAProduct').find('option[value='+isAProduct+']').attr('selected','selected');

                    //方法2
                    var optionsLength = document.getElementById('productType').options.length;
                    var pt = document.getElementById('productType');

                    for(var i = 0; i < optionsLength; i++){
                        var option = parseInt(document.getElementById('productType').options[i].value);
                        if(option == productType){
                            pt.options[i].setAttribute("selected","true");
                        }
                    }


                    var aLength = document.getElementById('isAProduct').options.length;
                    var ap = document.getElementById('isAProduct');

                    for(var j = 0; j < aLength; j++){
                        var optionA = parseInt(document.getElementById('isAProduct').options[j].value);
                        if(optionA == isAProduct){
                            ap.options[j].setAttribute("selected","true");
                        }
                    }

                }
            }
        });
    }