我正在从数据库检索数据并在标签中显示。但问题是，这无法检索db tabel第一行数据。它将打印第二行数据。如果我给了db第一行c\U代码，那么它会出现错误“位置2没有行”，请解决我的问题。谢谢你
private void Get_Purchasing_Amount()
{
try
{
string get_P_Amount = "";
double var_P_Amount = 0;
int var_C_Code = 0;
string query = "select c_code as 'code' from `db_vegetable`.`tbl_payment_master`";
DataTable dt_C_Code = method_Class.method_Class.FetchRecords(query);
if (dt_C_Code.Rows.Count > 0)
{
for (int i = 0; i <= dt_C_Code.Rows.Count; i++)
{
var_C_Code = Convert.ToInt32(dt_C_Code.Rows[i]["code"]);
if (var_C_Code.Equals(Convert.ToInt32(txt_Customer_Code.Text)))
{
if (check_All.Checked.Equals(true))
{
get_P_Amount = "SELECT IFNULL(`purchasing`,0) AS 'purchasing' FROM `db_vegetable`.`tbl_payment_master` WHERE `c_code` = " + txt_Customer_Code.Text + "";
}
else
{
string dt_Query = "select `id` as 'id' from `db_vegetable`.`tbl_order_details`";
DataTable dt_C_O = method_Class.method_Class.FetchRecords(dt_Query);
if (dt_C_O.Rows.Count > 0)
get_P_Amount = "SELECT IFNULL(SUM(t_price),0) as 'purchasing' FROM `db_vegetable`.`tbl_order_details` WHERE `c_code` = " + txt_Customer_Code.Text + " AND (`date` BETWEEN '" + txt_From_Date.Text + "' AND '" + txt_To_Date.Text + "')";
else
lbl_Purchasing_Amount.Text = "0";
}
DataTable dt = method_Class.method_Class.FetchRecords(get_P_Amount);
var_P_Amount = Convert.ToDouble(dt.Rows[0]["purchasing"]);
lbl_Purchasing_Amount.Text = var_P_Amount.ToString();
}
else
{
lbl_Purchasing_Amount.Text = "0";
}
}
}
else
{
lbl_Purchasing_Amount.Text = "0";
}
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
}
2条答案
按热度按时间eoxn13cs1#
现在的问题是解决问题就是那个破关键词。
cpjpxq1n2#
我相信这可能就是问题所在：
for (int i = 0; i <= dt_C_Code.Rows.Count; ; i++) {...}请考虑替换foreach (DataRow row in dt_C_Code.Rows) { ...}如果哪一行逻辑上应该排在“第一”位很重要，那么请考虑使用order bysql语句中的子句。