我过去遇到过这个问题。我正在使用 PostgreSQL,运行程序时,有时会连接,有时会引发类似错误。
当我尝试自己的代码时,我将“连接”代码放在公共表单下方的第一行。这是一个例子:
之前:
public Form1()
{
//HERE LIES SOME CODES FOR RESIZING MY CONTROLS DURING RUNTIME
//CODE
//CODE AGAIN
//ANOTHER CODE
//CODE NA NAMAN
//CODE PA RIN!
//Connect to Database to generate auto number
NpgsqlConnection iConnect = new NpgsqlConnection("Server=localhost;Port=5432;User ID=postgres;Password=pass;Database=DB");
iConnect.Open();
NpgsqlCommand iQuery = new NpgsqlCommand("Select * from table1", iConnect);
NpgsqlDataReader iRead = iQuery.ExecuteReader();
NpgsqlDataAdapter iAdapter = new NpgsqlDataAdapter(iQuery);
DataSet iDataSet = new DataSet();
iAdapter.Fill(iDataSet, "ID");
MessageBox.Show(iDataSet.Tables["ID"].Rows.Count.ToString());
}
现在:
public Form1()
{
//Connect to Database to generate auto number
NpgsqlConnection iConnect = new NpgsqlConnection("Server=localhost;Port=5432;User ID=postgres;Password=pass;Database=DB");
iConnect.Open();
NpgsqlCommand iQuery = new NpgsqlCommand("Select * from table1", iConnect);
NpgsqlDataReader iRead = iQuery.ExecuteReader();
NpgsqlDataAdapter iAdapter = new NpgsqlDataAdapter(iQuery);
DataSet iDataSet = new DataSet();
iAdapter.Fill(iDataSet, "ID");
MessageBox.Show(iDataSet.Tables["ID"].Rows.Count.ToString());
//HERE LIES SOME CODES FOR RESIZING MY CONTROLS DURING RUNTIME
//CODE
//CODE AGAIN
//ANOTHER CODE
//CODE NA NAMAN
//CODE PA RIN!
}
我认为该程序必须先读取连接,然后再执行任何操作,我不知道,如果我做错了,请更正我。但是根据我的研究,这不是代码问题-实际上是机器本身造成的。
编码愉快!