如何显示两位小数的DataGridView列和TextBoxes？

Question

我想知道当我从sqlserver两个表中将它们加载到DataGridView和TextBoxes时如何将值转换为两位小数。这是我的代码。我尝试了txtgrandTotal.Text = Total.ToString（＆＃34;＃， 0.00＆＃34;）代码，当我将数据插入数据库

时

 public void loadDataToUpdate()
    {

        DynamicConnection con = new DynamicConnection();

        try
        {
            con.sqlquery("SELECT p.PO_No,p.Supplier_ID,p.Date,p.RequiredDate,p.GrandTotal,b.BookName,c.ISBN_No,c.OrderQuantity,c.UnitPrice,c.Total FROM  TBL_PO_Cart AS c INNER JOIN TBL_Book AS b ON c.ISBN_No = b.ISBN_No INNER JOIN TBL_PO AS p ON c.PO_No=p.PO_No where p.PO_No='" + cmbPO.Text + "'");
            con.mysqlconnection();
            con.datatable();
            SqlDataAdapter da = new SqlDataAdapter(con.cmd);
            DataSet ds = new DataSet();
            da.Fill(ds);
            for (int i = 0; i < ds.Tables[0].Rows.Count; i++)
            {
                txtPONo.Text = ds.Tables[0].Rows[i][0].ToString();
                cmbsupID.Text = ds.Tables[0].Rows[i][1].ToString();
                date1.Text = ds.Tables[0].Rows[i][2].ToString();
                requireddate.Text = ds.Tables[0].Rows[i][3].ToString();
                txtgrandTotal.Text = (ds.Tables[0].Rows[i][4].ToString());
            }
            con.dataread();
            this.dataGridView1.Rows.Clear();
            while (con.datareader.Read())
            {
                DataGridViewRow row = (DataGridViewRow)dataGridView1.Rows[0].Clone();
                row.Cells[0].Value = con.datareader["BookName"].ToString();
                row.Cells[1].Value = con.datareader["ISBN_No"].ToString();
                row.Cells[2].Value = con.datareader["OrderQuantity"].ToString();
                row.Cells[3].Value = con.datareader["UnitPrice"].ToString();
                row.Cells[4].Value = con.datareader["Total"].ToString();
                dataGridView1.Rows.Add(row);
            }
        }

所以我需要显示txtgrandTotal文本框，datagridview column3和column4，带有2位小数。请帮帮我