关于DataTable的一点意外用法

假如有如下数据：

id curr next

1 A B

1 B C

1 C D

1 D E

1 E F

假如知道ID＝1和curr=B,求最后一个节点E

DataTable dt = new DataTable();

dt.Columns.Add("ID");

dt.Columns.Add("CURR");

dt.Columns.Add("NEXT");

DataRow dr1 = dt.NewRow();

dr1["ID"] = "1";

dr1["CURR"] = "A";

dr1["NEXT"] = "B";

dt.Rows.Add(dr1);

dr1 = dt.NewRow();

dr1["ID"] = "1";

dr1["CURR"] = "B";

dr1["NEXT"] = "C";

dt.Rows.Add(dr1);

dr1 = dt.NewRow();

dr1["ID"] = "1";

dr1["CURR"] = "C";

dr1["NEXT"] = "D";

dt.Rows.Add(dr1);

dr1 = dt.NewRow();

dr1["ID"] = "1";

dr1["CURR"] = "D";

dr1["NEXT"] = "E";

dt.Rows.Add(dr1);

dr1 = dt.NewRow();

dr1["ID"] = "1";

dr1["CURR"] = "E";

dr1["NEXT"] = "F";

dt.Rows.Add(dr1);

string strCurr = "B";

DataRow[] drs = dt.Select("CURR='" + strCurr + "'");

for (;drs.Length != 0;)

{

if (drs[0]["curr"].ToString() == "E")

{

Response.Write(drs[0]["curr"].ToString());

break;

}

strCurr = drs[0]["next"].ToString();

drs = dt.Select("CURR='" + strCurr + "'");

}