数据层级展示

来源：互联网发布：淘宝太坑缩水扣不了编辑：程序博客网时间：2024/05/18 18:18

今天遇到一个问题，就是要把一个有层级关系的数据表的数据用层级的方式展示出来（不是用TreeView），而是在下拉框中展示出来，真的很BT的需求，但是还是要实现的是不，不说废话了，下面就是具体做法

//1.在现有的数据中加一个表示这条数据深度（第几层）的列

在这里，dt是已经充满数据的一个DataTable

//克隆一个表，加上Depth（深度列）

DataTable clondt = dt.Copy();
clondt.Columns.Add("Depth");

MakeTree(dt, clondt);//填充一条数据的深度值

DataTable newdt = clondt.Clone();
SetNewTable(newdt, clondt);//真正的填充层级数据

//2.取得这个深度值，代码如下：

/// <summary>
        /// 填充节点层级
        /// </summary>
        /// <param name="dt"></param>
        /// <param name="clondt"></param>
        private static void MakeTree(DataTable dt, DataTable clondt)
        {
            for (int i = 0; i < dt.Rows.Count; i++)
            {
                int depth = 1;
                if (dt.Rows[i]["PARENTCOMPANYID"] != DBNull.Value)
                {
                    depth++;
                    int parentcompanyId = Convert.ToInt32(dt.Rows[i]["PARENTCOMPANYID"]);
                    while (HaveLoopParent(dt, ref parentcompanyId))
                    {
                        depth++;
                    }
                }
                clondt.Rows[i]["Depth"] = depth;
            }
        }

        private static bool HaveLoopParent(DataTable dt, ref int parentcompanyId)
        {
            DataRow[] drs = dt.Select("COMPANYID=" + parentcompanyId);

            if (drs.Length > 0)
            {
                if (drs[0]["PARENTCOMPANYID"] == DBNull.Value)
                    return false;
                else
                {
                    parentcompanyId = Convert.ToInt32(drs[0]["PARENTCOMPANYID"]);
                    return true;
                }
            }
            else
                return false;
        }

//3.填充层级数据

/// <summary>
        /// 把层级关系赋值给新的表
        /// </summary>
        /// <param name="newdt"></param>
        /// <param name="clondt"></param>
        private static void SetNewTable(DataTable newdt, DataTable clondt)
        {
            DataRow rootRow = clondt.Select("PARENTCOMPANYID IS NULL")[0];
            SetNewRow(newdt, rootRow);

GetChild(rootRow, clondt, newdt);
}

        private static void SetNewRow(DataTable newdt, DataRow rootRow)
        {
            DataRow row = newdt.NewRow();
            if (rootRow["Depth"] != DBNull.Value)
            {
                string line = "";
                for (int i = 0; i < Convert.ToInt32(rootRow["Depth"]); i++)
                {
                    line += "| ";
                }
                row["COMPANYNAME"] = line + "-" + rootRow["COMPANYNAME"];
            }
            row["COMPANYID"] = rootRow["COMPANYID"];
            row["COMPANYNO"] = rootRow["COMPANYNO"];
            row["COMPANYCODE"] = rootRow["COMPANYCODE"];
            row["RECORDSTATUS"] = rootRow["RECORDSTATUS"];
            row["MODIFYUSERID"] = rootRow["MODIFYUSERID"];
            row["MODIFYDATE"] = rootRow["MODIFYDATE"];
            row["PARENTCOMPANYNO"] = rootRow["PARENTCOMPANYNO"];
            row["CreateDate"] = rootRow["CreateDate"];
            row["ModifiedOn"] = rootRow["ModifiedOn"];
            row["PARENTCOMPANYID"] = rootRow["PARENTCOMPANYID"];
            row["Depth"] = rootRow["Depth"];
            newdt.Rows.Add(row);
        }

        private static void GetChild(DataRow rootRow, DataTable clondt, DataTable newdt)
        {
            DataRow[] childrows = clondt.Select("PARENTCOMPANYID=" + rootRow["COMPANYID"]);
            for (int i = 0; i < childrows.Length; i++)
            {
                DataRow childrow = childrows[i];

SetNewRow(newdt, childrow);

                if (clondt.Select("PARENTCOMPANYID=" + childrow["COMPANYID"]).Length > 0)
                {
                    GetChild(childrow, clondt, newdt);
                }
            }
        }