C# 使用listview外部的按钮从listview插入数据

我正在清单表中添加来自listview中输入的状态。如果数量超过临界水平，我想将状态更改为可用，但不会添加任何状态

我试过这个密码。它正在添加库存，但我的状态似乎仍然为空

protected void btnAdd_Click(object sender, EventArgs e)
{
    bool existingSupply = IsExisting();


    foreach (ListViewItem item in lvPODetails.Items)
    {

        var inventory = new DataTable();
        using (var da = new SqlDataAdapter("SELECT * FROM Inventory", con))
        {
            da.Fill(inventory);
        }

        var products = new DataTable();
        using (var da = new SqlDataAdapter("SELECT * FROM SupplierProducts", con))
        {
            da.Fill(products);
        }

        TextBox quantity = (TextBox)item.FindControl("txtQuantity");
        Label ltr = (Label)item.FindControl("lblProduct");
        TextBox odr = (TextBox)item.FindControl("txtOrdered");

        string name = ltr.Text;
        int delivered = Convert.ToInt32(quantity.Text);
        int ordered = Convert.ToInt32(odr.Text);
        string status = String.Empty;
        string InventStatus = String.Empty;

        int finalQuantity = Convert.ToInt32(inventory.Rows[0]["Quantity"]) + delivered;
        int criticalLevel = Convert.ToInt32(products.Rows[0]["CriticalLevel"]);

        if (finalQuantity <= criticalLevel && finalQuantity != 0)
        {
            InventStatus = "Critical";
        }
        else if (finalQuantity > criticalLevel)
        {
            InventStatus = "Available";
        }
        else
        {
            InventStatus = "Unavailable";
        }

        if (delivered >= ordered)
        {
            status = "Complete";

        }




        if (delivered < ordered)
        {
            status = "Partially Completed";

        }

        con.Open();
        SqlCommand cmd = new SqlCommand();
        cmd.Connection = con;
        if (existingSupply)
        {
            cmd.CommandText = "UPDATE Inventory SET Quantity=quantity + @Quantity, DateModified=@DateModified WHERE ProductID=@ProductID";

        }

        else
        {

            cmd.CommandText = "INSERT INTO Inventory VALUES (@ProductID, @SupplierID, " +
                "@Quantity, @CriticalLevel, @Price, @Status, @UserID, @DateAdded)";

        }

        cmd.Parameters.AddWithValue("@ProductID", name);     
        cmd.Parameters.AddWithValue("@SupplierID", txtSupplierID.Text);
        cmd.Parameters.AddWithValue("@Quantity", delivered);
        cmd.Parameters.AddWithValue("@CriticalLevel", DBNull.Value);
        cmd.Parameters.AddWithValue("@Price", DBNull.Value);
        cmd.Parameters.AddWithValue("@Status", InventStatus);
        cmd.Parameters.AddWithValue("@UserID", Session["userid"].ToString());
        cmd.Parameters.AddWithValue("@DateAdded", DateTime.Now);
        cmd.Parameters.AddWithValue("@DateModified", DateTime.Now);
        cmd.ExecuteNonQuery();

        cmd = new SqlCommand();
        cmd.Connection = con;
        cmd.CommandText = "UPDATE PurchaseOrder SET POStatus=@POStatus WHERE PONo=@PONo";
        cmd.Parameters.AddWithValue("@POStatus", status);
        cmd.Parameters.AddWithValue("@PONo", txtPONo.Text);
        cmd.ExecuteNonQuery();
        con.Close();

    }
    Response.Redirect("Default.aspx");         
} 

它显示了这样的结果

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代码中唯一缺少的是，它调用行中的第一个。我只是添加了一个where语句和要选择的ID