在c#form application中更新访问mdb数据库中的数据"update statement中的语法错误"

Question

我在C#表单应用程序中使用MS-Access mdb数据库.我有一个数据库,我有一个表Customers有两列CustomerId和Balance.两列都是integer数据类型.

我得到的错误是

System.Data.OleDb.OleDbException:UPDATE语句中的语法错误.

System.Data.OleDb.OleDbCommand.ExecuteCommandTextForSingleResult(tagDBPARAMS dbParams,Object&executeResult)的System.Data.OleDb.OleDbCommand.ExecuteCommandTextErrorHandling(OleDbHResult hr)处于System.Data的
System.Data.OleDb.OleDbCommand.ExecuteCommandText(Object&executeResult)
.
位于System.Data.OleDb.OleDbCommand.ExecuteNonQuery()的System.Data.OleDb.OleDbCommand.ExecuteReaderInternal(CommandBehavior behavior,String方法)
中的OleDb.OleDbCommand.ExecuteCommand(CommandBehavior behavior,Object&executeResult)
xml_and_db_test.Form1.button1_Click(Object sender ,EventArgs e)在G:\ my Documents\Visual Studio 2008\Projects\xml_and_db_test\xml_and_db_test\Form1.cs:第45行

我到现在为止尝试的代码是

try
{
   OleDbConnection con = new 
   OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=|DataDirectory|\\database_for_kissan_Pashu_AhaR_Bills.mdb");

   int balance = Convert.ToInt32(textBox2.Text);
   int id = Convert.ToInt32(textBox1.Text);

   // int recordnumb = int.Parse(recordTextBox.Text);

   //  OleDbConnection oleDbConnection = new            OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;Data Source=C:\\Users\\Checkout-1\\Documents\\contact.accdb");    
   OleDbCommand update = new OleDbCommand("UPDATE Customers  SET Balance = '" + balance + "',  WHERE id = " + id + " ", con);

   con.Open();
   update.ExecuteNonQuery();
   con.Close();

   // string queryText = "UPDATE Customers SET Balance = ?, where CustomerId = ?;";
   //string queryText = " 'UPDATE Customers SET Balance =' " + balance+ " ' WHERE CustomerId=  ' " +  id +  " ' " ;

   //OleDbCommand cmd = new OleDbCommand(queryText, con);
   //cmd.CommandType = CommandType.Text;
   //cmd.Parameters.AddWithValue("@balance", Convert.ToInt32(textBox2.Text));
   //cmd.Parameters.AddWithValue("@ID", Convert.ToInt32(textBox1.Text));
   //cmd.Parameters.Add("Balance", OleDbType.Integer).Value = Convert.ToInt32(textBox2.Text);
   //cmd.Parameters.Add("CustomerId", OleDbType.Integer).Value = Convert.ToInt32(textBox1.Text);

   //con.Open(); // open the connection
   ////OleDbDataReader dr = cmd.ExecuteNonQuery();

   //int yy = cmd.ExecuteNonQuery();
   //con.Close();
}
catch (Exception ex)
{
    string c = ex.ToString();
    MessageBox.Show(c);
}

//try
//{
//    OleDbConnection con = new OleDbConnection("Provider = Microsoft.Jet.OLEDB.4.0; Data Source = G:\\my Documents\\Visual Studio 2008\\Projects\\xml_and_db_test\\xml_and_db_test\\bin\\Debug\\database_for_kissan_Pashu_AhaR_Bills.mdb");
//    string queryText = "UPDATE Customers SET Balance = ?, where CustomerId = ?;";

//    OleDbCommand cmd = new OleDbCommand(queryText, con);
//    cmd.CommandType = CommandType.Text;
//    //cmd.Parameters.AddWithValue("@balance", Convert.ToInt32(textBox2.Text));
//    //cmd.Parameters.AddWithValue("@ID", Convert.ToInt32(textBox1.Text));

//    cmd.Parameters.Add("Balance", OleDbType.Integer).Value = Convert.ToInt32(textBox2.Text);

//    cmd.Parameters.Add("CustomerId", OleDbType.Integer).Value = Convert.ToInt32(textBox1.Text);
//    con.Open(); // open the connection
//    //OleDbDataReader dr = cmd.ExecuteNonQuery();

//    int yy = cmd.ExecuteNonQuery();
//    con.Close();

//}
//catch (Exception ex)
//{
//    string c = ex.ToString();
//    MessageBox.Show(c);

//}
//string connetionString = null;
//OleDbConnection connection;
//OleDbDataAdapter oledbAdapter = new OleDbDataAdapter();
//string sql = null;
//connetionString = "Provider = Microsoft.Jet.OLEDB.4.0; Data Source = G:\\my Documents\\Visual Studio 2008\\Projects\\xml_and_db_test\\xml_and_db_test\\bin\\Debug\\database_for_kissan_Pashu_AhaR_Bills.mdb;";
//connection = new OleDbConnection(connetionString);
//sql = "update Customers set Balance = '1807' where CustomerId = '1'";
//try
//{
//    connection.Open();
//    oledbAdapter.UpdateCommand = connection.CreateCommand();
//    oledbAdapter.UpdateCommand.CommandText = sql;
//    oledbAdapter.UpdateCommand.ExecuteNonQuery();
//    MessageBox.Show("Row(s) Updated !! ");
//    connection.Close();
//}
//catch (Exception ex)
//{
//    MessageBox.Show(ex.ToString());
//}

一些代码在注释中,有些代码与每种方法都有相同的错误.

Answer 1

正如gzaxx所说..尝试改变这一点

string queryText = "UPDATE Customers SET Balance = ?, where CustomerId = ?;";

同

string queryText = "UPDATE Customers SET Balance = ? where CustomerId = ?;";