添加来自独立DataRow[] select查询的值

我试图从一个数据库与两个单独的datarow拉两个值，并将它们加在一起。出于某种原因，我不知道我做错了什么，但变量p1和p2显示为未赋值当我试图将它们加在一起时。

        int p1;
        int p2;
        string count;
        DataRow[] p1Count = dtCount.Select("ATTID = '" + att + " and WAVID = '20111'");
        foreach (DataRow row in p1Count)
        {
            p1 = int.Parse(row["CountValue"].ToString());
        }
        DataRow[] p2Count = dtCount.Select("ATTID = '" + att + " and WAVID = '20112'");
        foreach (DataRow row in p2Count)
        {
            p2 = int.Parse(row["CountValue"].ToString());
        }
        count = (p1 + p2).ToString();
        sb.Append("<td nowrap ALIGN=CENTER colspan='1' bordercolor=#fff><strong>" + count + "</strong></td>");

int p1;
int p2;

int p1 = 0;
int p2 = 0;