我是C#的新手.
请协助！
请协助！
我一直有以下错误：“ExecuteNonQuery需要一个开放且可用的连接.连接的当前状态已关闭.”
我也无法插入我的数据库.
以下是我的代码：
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Data.OleDb;
namespace AzureSecureStore
{
public partial class Client : Form
{
OleDbConnection vcon = new OleDbConnection(@"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=C:\Users\SB18\Documents\Visual Stu@R_404_410@ 2010\Projects\AzureSecureStore\AzureSecureStore\AzcureSecureStore Database.accdb; Persist Security Info=False;");
//OleDbConnection vcon = new OleDbConnection(@"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=C:\Users\SB18\Documents\Visual Stu@R_404_410@ 2010\Projects\AzureSecureStore\AzureSecureStore\AzcureSecureStore Database.accdb");
public Client()
{
InitializeComponent();
}
private void button1_Click(object sender,EventArgs e)
{
}
private void dataGridView1_CellContentClick(object sender,DataGridViewCellEventArgs e)
{
}
private void button5_Click(object sender,EventArgs e)
{
}
private void button4_Click(object sender,EventArgs e)
{
}
private void Client_Load(object sender,EventArgs e)
{
// TODO: This line of code loads data into the 'azcureSecureStore_DatabaseDataSet5.Client' table. You can move,or remove it,as needed.
this.clientTableAdapter.Fill(this.azcureSecureStore_DatabaseDataSet5.Client);
// TODO: This line of code loads data into the 'azcureSecureStore_DatabaseDataSet2.Client' table. You can move,as needed.
//this.clientTableAdapter.Fill(this.azcureSecureStore_DatabaseDataSet2.Client);
}
private void button2_Click(object sender,EventArgs e)
{
string ab = string.Format("insert into Client values({0},'{1}','{2}',{3},{4},'{5}')",textBox1.Text,textBox2.Text,int.Parse(textBox3.Text),int.Parse(textBox4.Text),textBox9.Text,int.Parse(textBox10.Text));
OleDbCommand vcom = new OleDbCommand(ab,vcon);
vcom.ExecuteNonQuery();
MessageBox.Show("Data stored successfully");
vcom.Dispose();
}
private void textBox1_TextChanged(object sender,EventArgs e)
{
}
}
}
解决方法
你忘了打开连接,
vcon.Open(); vcom.ExecuteNonQuery();
但记得要用
> using statement – 正确处理对象
> try-catch块 – 正确捕获异常(异常处理)
更新1
string connStr = @"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=C:\Users\SB18\Documents\Visual Stu@R_404_410@ 2010\Projects\AzureSecureStore\AzureSecureStore\AzcureSecureStore Database.accdb; Persist Security Info=False;"; string query = "INSERT INTO Client VALUES(@col1,@col2,@col3,@col4,@col5,@col6)"; using (OleDbConnection conn = new OleDbConnection(connStr)) { using (OleDbCommand comm = new OleDbCommand()) { comm.Connection = conn; comm.CommandText = query; comm.CommandType = CommandType.Text; comm.Parameters.AddWithValue("@col1",textBox1.Text); comm.Parameters.AddWithValue("@col2",textBox2.Text); comm.Parameters.AddWithValue("@col3",int.Parse(textBox3.Text)); comm.Parameters.AddWithValue("@col4",int.Parse(textBox4.Text)); comm.Parameters.AddWithValue("@col5",textBox9.Text); comm.Parameters.AddWithValue("@col6",int.Parse(textBox10.Text)); try { conn.Open(); comm.ExecuteNonQuery(); MessageBox.Show("Data stored successfully"); } catch(OleDbException e) { MessageBox.Show(e.ToString()); } } }
