DataTable table=new DataTable();
        //。。。。加入获取数据的代码
    
        DataColumn col = new DataColumn("时间间隔", typeof(string));
        table.Columns.Add(col);

        for(int i=0;i<table.Rows.Count-1;i++)
        {
            DateTime dt1 = DateTime.Parse(table.Rows[i][2].ToString());
            DateTime dt2 = DateTime.Parse(table.Rows[i+1][2].ToString());

            TimeSpan span = dt2 - dt1;
            string str = string.Format("{0}{1}",span.Days,span.Hours);
            table.Rows[i + 1][3] = str;   //注意正确列索引！
        }

------解决方案--------------------
C# code
   private void dataGridView1_CellFormatting(object sender, DataGridViewCellFormattingEventArgs e)
        {
            string dateDiff = "";
            if (e.ColumnIndex == 2)
            { 
                if (e.RowIndex >0)
                {
                DataGridViewRow row = this.dataGridView1.Rows[e.RowIndex];             
                 DataGridViewRow row2 = this.dataGridView1.Rows[e.RowIndex - 1];
                 if (row != null && row2!=null)
                {
                    if (row.Cells["create_date"].Value.ToString() != "" && row.Cells["create_date"].Value!= null)
                    {
                        DateTime dt1=Convert.ToDateTime(row.Cells["create_date"].Value.ToString());                        
                        DateTime dt2=Convert.ToDateTime(row2.Cells["create_date"].Value.ToString());
                        TimeSpan ts1 = new TimeSpan(dt1.Ticks);
                        TimeSpan ts2 = new TimeSpan(dt2.Ticks);
                        TimeSpan ts = ts1.Subtract(ts2).Duration();
                        if (int.Parse(ts.Days.ToString()) > 0)
                        {
                            dateDiff += ts.Days.ToString() + "天";
                        }
                        if (int.Parse(ts.Hours.ToString()) > 0)
                        {
                            dateDiff += ts.Hours.ToString() + "小时";
                        }
                        e.Value = dt1.ToString() +"    "+dateDiff;
                    }else
                    {
                    e.Value=row.Cells["create_date"].Value.ToString() ;
                    }
                }
                }

------解决方案--------------------

SQL code
CREATE TABLE TB (id INT IDENTITY(1,1),[name] VARCHAR(20),[time] VARCHAR(20))
INSERT INTO dbo.TB
SELECT '张三', '2011/8/18 15:47' UNION ALL
SELECT '李四', '2011/8/19 19:47' UNION ALL
SELECT '王五', '2011/8/20 20:47' UNION ALL
SELECT '麻子', '2011/8/21 22:27'

SELECT  a.* ,ISNULL(LTRIM(DATEDIFF(HOUR, b.time, a.time) / 24) + '天' + 
        LTRIM(DATEDIFF(HOUR, b.time,a.time) % 24) + '小時','') AS '處理時間'
FROM    dbo.TB a
        LEFT JOIN dbo.TB b ON a.id = b.id + 1

DROP TABLE dbo.TB
/*
id          name                 time                 處理時間
----------- -------------------- -------------------- ------------------------------
1           张三                   2011/8/18 15:47      
2           李四                   2011/8/19 19:47      1天4小時
3           王五                   2011/8/20 20:47      1天1小時
4           麻子                   2011/8/21 22:27      1天2小時

(4 個資料列受到影