我正在尝试直接在datagridview上编辑数据库中的数据，但由于某些原因我遇到了错误。
对象引用未设置为对象的实例
我尝试了一些不同的方法，但没有奏效，有同样的错误。
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.Data.Sql;
using System.Data.SqlClient;
using System.Threading;
using System.Runtime.InteropServices;
namespace WindowsFormsApplication2
{
public partial class Principal : Form
{
SqlConnection con;
SqlDataAdapter adap;
SqlCommandBuilder scb;
DataSet ds;
SqlCommandBuilder cmdb1;
public Principal()
{
InitializeComponent();
Load += new EventHandler(Principal_Load);
}
private void fusionButton1_Click(object sender, EventArgs e)
{
AdicionarFornecedor add = new AdicionarFornecedor();
add.ShowDialog();
}
private void fusionButton2_Click(object sender, EventArgs e)
{
VerFornecedores add = new VerFornecedores();
add.ShowDialog();
}
private void Principal_Load(object sender, EventArgs e)
{
try
{
SqlConnection con;
SqlDataAdapter adap;
DataSet ds;
con = new SqlConnection();
con.ConnectionString = (@"Data Source=(LocalDB)\MSSQLLocalDB;AttachDbFilename=|DataDirectory|PAPPloran.mdf;Integrated Security=True;Connect Timeout=30");
con.Open();
adap = new SqlDataAdapter("select * from Pagamentos", con);
ds = new System.Data.DataSet();
adap.Fill(ds, "P");
dataGridView1.DataSource = ds.Tables[0];
}
catch (Exception ex)
{
MessageBox.Show("Erro\n" + ex.Message, "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
}
}
private void fusionTheme1_Click(object sender, EventArgs e)
{
}
private void fusionButton3_Click(object sender, EventArgs e)
{
AdicionarPagamento add2 = new AdicionarPagamento();
add2.ShowDialog();
}
private void fusionButton4_Click(object sender, EventArgs e)
{
SqlConnection con = new SqlConnection(@"Data Source=(LocalDB)\MSSQLLocalDB;AttachDbFilename=|DataDirectory|PAPPloran.mdf;Integrated Security=True;Connect Timeout=30");
con.Open();
SqlCommand cmd = new SqlCommand(@"delete from Pagamentos WHERE (IdFornecedor = '" + textBox3.Text + "')", con);
cmd.ExecuteNonQuery();
MessageBox.Show("Dados Eliminados com Sucesso ! ");
textBox3.Text = "";
con.Close();
}
private void textBox1_TextChanged(object sender, EventArgs e)
{
}
private void textBox1_KeyUp(object sender, KeyEventArgs e)
{
con = new SqlConnection();
con.ConnectionString = (@"Data Source=(LocalDB)\MSSQLLocalDB;AttachDbFilename=|DataDirectory|PAPPloran.mdf;Integrated Security=True;Connect Timeout=30");
con.Open();
SqlCommand cmd = con.CreateCommand();
cmd.CommandType = CommandType.Text;
cmd.CommandText = "select * from Pagamentos where NomeFornecedor like ('" + textBox1.Text + "%')";
cmd.ExecuteNonQuery();
DataTable dt = new DataTable();
SqlDataAdapter da = new SqlDataAdapter(cmd);
da.Fill(dt);
dataGridView1.DataSource = dt;
con.Close();
}
private void dataGridView1_CellContentClick(object sender, DataGridViewCellEventArgs e)
{
}
private void fusionButton5_Click(object sender, EventArgs e)
{
foreach (DataGridViewRow row in dataGridView1.Rows)
if (row.Cells[7].Value != null && row.Cells[7].Value.ToString() == "1- Pago")
{
row.DefaultCellStyle.BackColor = Color.GreenYellow;
}
else
{
row.DefaultCellStyle.BackColor = Color.Tomato;
}
}
public const int WM_NCLBUTTONDOWN = 0xA1;
public const int HT_CAPTION = 0x2;
[DllImportAttribute("user32.dll")]
public static extern int SendMessage(IntPtr hWnd, int Msg, int wParam, int lParam);
[DllImportAttribute("user32.dll")]
public static extern bool ReleaseCapture();
private void fusionTheme1_MouseDown(object sender, MouseEventArgs e)
{
ReleaseCapture();
SendMessage(this.Handle, WM_NCLBUTTONDOWN, HT_CAPTION, 0);
}
private void fusionButton6_Click(object sender, EventArgs e)
{
this.Close();
}
private void button1_Click(object sender, DataGridViewCellFormattingEventArgs e)
{
}
private void fusionButton7_Click(object sender, EventArgs e)
{
SqlConnection con;
SqlDataAdapter adap;
DataSet ds;
con = new SqlConnection();
con.ConnectionString = (@"Data Source=(LocalDB)\MSSQLLocalDB;AttachDbFilename=|DataDirectory|PAPPloran.mdf;Integrated Security=True;Connect Timeout=30");
con.Open();
adap = new SqlDataAdapter("select * from Pagamentos", con);
ds = new System.Data.DataSet();
adap.Fill(ds, "P");
dataGridView1.DataSource = ds.Tables[0];
}
private void fusionButton8_Click(object sender, EventArgs e)
{
con.ConnectionString = (@"Data Source=(LocalDB)\MSSQLLocalDB;AttachDbFilename=|DataDirectory|PAPPloran.mdf;Integrated Security=True;Connect Timeout=30");
con.Open();
SqlCommand cmd = new SqlCommand(@"delete from Pagamentos WHERE (NomeFornecedor = '" + textBox3.Text + "')", con);
cmd.ExecuteNonQuery();
MessageBox.Show("Dados Eliminados com Sucesso ! ");
textBox3.Text = "";
con.Close();
}
private void Principal_Load_1(object sender, EventArgs e)
{
}
private void fusionButton9_Click(object sender, EventArgs e)
{
try
{
cmdb1 = new SqlCommandBuilder(adap);
adap.Update(ds);
MessageBox.Show("Data updated", "Update", MessageBoxButtons.OK, MessageBoxIcon.Information);
}
catch (Exception ex)
{
MessageBox.Show(ex.Message, "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
}
}
}
}
