如何在c#中更新datagridview中的项

Question

我想更新发票，发票有多个项目，我从数据库中检索发票项目到DataGridView，现在用户可以删除项目并添加项目，用户将单击更新按钮更新数据库中的发票。

我的代码：

try
{
using (SQLiteConnection con = new SQLiteConnection(AppSettings.ConnectionString()))
{
con.Open();
for (int j = 0; j < dgv.Rows.Count; j++)
{
using (SQLiteCommand sc = new SQLiteCommand("Update Orders Set [Order_No] = @Order_No,[Order_Type] = @Order_Type,[Order_Date] = @Order_Date,[Customer_Name] = @Customer_Name,[Contact] = @Contact,[Adress] = @Adress,[Delivery_Address] = @Delivery_Address,[Rider] = @Rider,[Items] = @Items,[Price] = @Price,[Qty] = @Qty,[Item_Total] = @Item_Total,[Item_Cat] = @Item_Cat,[SubTotal] = @SubTotal,[Discount] = @Discount,[Total_Amount] = @Total_Amount,[Paid_Amount] = @Paid_Amount,[Change_Due] = @Change_Due,[Delivery_Charges] = @Delivery_Charges Where Order_No = '" + Order_No.Text + "' ", con))
{
sc.Parameters.AddWithValue("@Order_No", Order_No.Text);
sc.Parameters.AddWithValue("@Order_Type", Order_Type.Text);
sc.Parameters.AddWithValue("@Order_Date", Order_Date.Text);
sc.Parameters.AddWithValue("@Customer_Name", Customer_Name.Text);
sc.Parameters.AddWithValue("@Contact", Contact.Text);
sc.Parameters.AddWithValue("@Adress", Address.Text);
sc.Parameters.AddWithValue("@Delivery_Address", Delivery_Address.Text);
sc.Parameters.AddWithValue("@Rider", "");
sc.Parameters.AddWithValue("@Items", dgv.Rows[j].Cells[1].Value);
sc.Parameters.AddWithValue("@Price", dgv.Rows[j].Cells[2].Value);
sc.Parameters.AddWithValue("@Qty", dgv.Rows[j].Cells[3].Value);
sc.Parameters.AddWithValue("@Item_Total", dgv.Rows[j].Cells[4].Value);
sc.Parameters.AddWithValue("@Item_Cat", dgv.Rows[j].Cells[5].Value);
sc.Parameters.AddWithValue("@SubTotal", SubTotal.Text);
sc.Parameters.AddWithValue("@Discount", Discount.Text);
sc.Parameters.AddWithValue("@Total_Amount", Total_Amount.Text);
sc.Parameters.AddWithValue("@Paid_Amount", Paid_Amount.Text);
sc.Parameters.AddWithValue("@Change_Due", Change_Due.Text);
sc.Parameters.AddWithValue("@Delivery_Charges", Del_Charges.Text);
sc.ExecuteNonQuery();
}
}
SuccessBox sb = new SuccessBox();
sb.lbl_Change.Text = Change_Due.Text;
sb.label1.Text = "Successfully Updated";
sb.ShowDialog();
con.Close();
}
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}

如果我添加新项目并单击更新按钮，则此查询将用新项目替换我的所有旧项目。

假设我添加了三星S8，这样它就会将我的旧项目替换为三星S8。

结果是：

Samsung S8   1   $750
Samsung S8   1   $750
Samsung S8   1   $750
Samsung S8   1   $750

有办法做到这一点吗？

Answer 1

您必须设置OrderID参数才能更新所需的Item

Answer 2

这将通过DataGrid对象为您执行Insert、Update和Delete操作。

using System;  
using System.Data;  
using System.Windows.Forms;  
using System.Data.SqlClient;  
namespace InsertUpdateDeleteDemo  
{  
public partial class frmMain : Form  
{  
SqlConnection con= new SqlConnection("Data Source=.;Initial Catalog=Sample;Integrated Security=true;");  
SqlCommand cmd;  
SqlDataAdapter adapt;  
//ID variable used in Updating and Deleting Record  
int ID = 0;  
public frmMain()  
{  
InitializeComponent();  
DisplayData();  
}  
//Insert Data  
private void btn_Insert_Click(object sender, EventArgs e)  
{  
if (txt_Name.Text != "" && txt_State.Text != "")  
{  
cmd = new SqlCommand("insert into tbl_Record(Name,State) values(@name,@state)", con);  
con.Open();  
cmd.Parameters.AddWithValue("@name", txt_Name.Text);  
cmd.Parameters.AddWithValue("@state", txt_State.Text);  
cmd.ExecuteNonQuery();  
con.Close();  
MessageBox.Show("Record Inserted Successfully");  
DisplayData();  
ClearData();  
}  
else  
{  
MessageBox.Show("Please Provide Details!");  
}  
}  
//Display Data in DataGridView  
private void DisplayData()  
{  
con.Open();  
DataTable dt=new DataTable();  
adapt=new SqlDataAdapter("select * from tbl_Record",con);  
adapt.Fill(dt);  
dataGridView1.DataSource = dt;  
con.Close();  
}  
//Clear Data  
private void ClearData()  
{  
txt_Name.Text = "";  
txt_State.Text = "";  
ID = 0;  
}  
//dataGridView1 RowHeaderMouseClick Event  
private void dataGridView1_RowHeaderMouseClick(object sender, DataGridViewCellMouseEventArgs e)  
{  
ID = Convert.ToInt32(dataGridView1.Rows[e.RowIndex].Cells[0].Value.ToString());  
txt_Name.Text = dataGridView1.Rows[e.RowIndex].Cells[1].Value.ToString();  
txt_State.Text = dataGridView1.Rows[e.RowIndex].Cells[2].Value.ToString();  
}  
//Update Record  
private void btn_Update_Click(object sender, EventArgs e)  
{  
if (txt_Name.Text != "" && txt_State.Text != "")  
{  
cmd = new SqlCommand("update tbl_Record set Name=@name,State=@state where ID=@id", con);  
con.Open();  
cmd.Parameters.AddWithValue("@id", ID);  
cmd.Parameters.AddWithValue("@name", txt_Name.Text);  
cmd.Parameters.AddWithValue("@state", txt_State.Text);  
cmd.ExecuteNonQuery();  
MessageBox.Show("Record Updated Successfully");  
con.Close();  
DisplayData();  
ClearData();  
}  
else  
{  
MessageBox.Show("Please Select Record to Update");  
}  
}  
//Delete Record  
private void btn_Delete_Click(object sender, EventArgs e)  
{  
if(ID!=0)  
{  
cmd = new SqlCommand("delete tbl_Record where ID=@id",con);  
con.Open();  
cmd.Parameters.AddWithValue("@id",ID);  
cmd.ExecuteNonQuery();  
con.Close();  
MessageBox.Show("Record Deleted Successfully!");  
DisplayData();  
ClearData();  
}  
else  
{  
MessageBox.Show("Please Select Record to Delete");  
}  
}  
}  
}