树状图组件数据转换

将有id和父级id的正常json数组改变为有children内嵌字段的方法（俄罗斯套娃，可用于树形控件和树形表格的生成，纯js原生代码，不需要其它依赖）

treeDataFormat(data, idField, parIdField, textField, openClose, rootId) {
                idField = idField || "id";//目标依据id
                parIdField = parIdField || "parent_id";//父级id
                textField = textField || "name";//文本字段
                rootId = rootId || 0;
                if (data && data.length > 0) {
                var dataMapping = {};
                for (var i = 0; i < data.length; i++) {
                    // dataMapping[data[i][idField]] = $.extend({}, data[i]);
                    dataMapping[data[i][idField]] = data[i];
                    //            dataMapping[data[i][idField]].children = [];
                    dataMapping[data[i][idField]].text = dataMapping[data[i][idField]][textField];
                    dataMapping[data[i][idField]].state = openClose || "open";
                }
                //构造上下级关系
                for (var i = 0; i < data.length; i++) {
                    var tempData = data[i];
                    if (tempData[parIdField] && dataMapping[tempData[parIdField]]) {
                    dataMapping[tempData[parIdField]].children = dataMapping[tempData[parIdField]].children || [];
                    dataMapping[tempData[parIdField]].children.push(dataMapping[tempData[idField]]);
                    }
                }
                var treeArray = [];
                for (var key in dataMapping) {
                    if (dataMapping[key].child_count != null || dataMapping[key].child_count != undefined) {
                    //查询出已明确定义子节点的数目
                    if (dataMapping[key].child_count > 0) { //有子节点
                        if (!dataMapping[key].children || dataMapping[key].children.length == 0) {
                        dataMapping[key].state = "closed";
                        } else {
                        dataMapping[key].state = "open";
                        }
                    } else { //无子节点
                        dataMapping[key].state = "open";
                    }
                    } else {
                    if (!dataMapping[key].children || dataMapping[key].children.length == 0) {
                        dataMapping[key].state = "open";
                    }
                    }
                    if (dataMapping[rootId]) {} else {
                    if (dataMapping[key][parIdField] == rootId) {
                        treeArray.push(dataMapping[key]);
                    }
                    }
                }
                if (dataMapping[rootId]) {
                    treeArray.push(dataMapping[rootId]);
                }
                return treeArray;
                }
                return [];
            };