C#中插入access数据库中的数据提示insert into 语法错误
string strConn = @"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=C:\Users\dell\Desktop\测量平差\测量间接评差\测量间接评差\bin\Debug\测量评差数据.accdb";
OleDbConnection myConn = new OleDbConnection ( strConn );
myConn.Open ( );
if (myConn.State==ConnectionState.Open )
{MessageBox.Show("数据库连接成功!");}
string strupdate = " insert into 高程网数据 (高程网等级,高程网类型,定权方式,已知点个数,未知点个数,观测值个数 ) values ('" + Convert.ToString(this.grade.SelectedItem) + "' , '" + Convert.ToString(this.style.SelectedItem) + " ' , '" + Convert.ToString(this.weight.SelectedItem) + "' , '" + Convert.ToInt32(this.known.Text) + "' ,' " + Convert.ToInt32(this.unknown.Text) + " ',' " + Convert.ToInt32(this.observation.Text) + "') ";
OleDbCommand myCommand = new OleDbCommand ( strupdate , myConn );
try
{
myCommand.ExecuteNonQuery ();
MessageBox.Show("保存成功!");
}
catch (Exception err)
{ MessageBox.Show(err.Message); }
请问各位大神哪里语法错了?