Question

这是我连接和使用Access数据库的C＃代码。

using System.Data.OleDb;

var cb = new OleDbCommandBuilder(da);

DataRow dRow = ds1.Tables["Customer"].NewRow();

dRow[0] = textBox1.Text;
dRow[1] = textBox2.Text;
dRow[2] = textBox3.Text;

ds1.Tables["Customer"].Rows.Add(dRow);

da.Update(ds1, "Customer");

con.Close();

MessageBox.Show("Entry added");

但是行da.Update(ds1,"Customer");引发了异常：

ConnectionString属性尚未初始化。

Answer 1

我没有太好地关注你的问题，但是这里有一些示例代码可以帮助你弄清楚你想要做的事情。

为清楚起见：数据库名为“MyDb.accdb”，并有一个名为“Customer”的表，其中有两个字段“Name”和“Phone”。此示例假定数据库与可执行文件位于同一目录中。

private void AddCustomer(string customerName, string customerPhone)
{
    string name = customerName;
    string phone = customerPhone;

    // An easy way to determine the connection string to your database is to open the database from Visual Studio's 'Server Explorer'.
    // Then, from Server Explorer, view the Properties of the database - in the Properties you will see the "Connection String". 
    // You can/should replace the arbitrary part of the path with "|DataDirectory|".
    string connString = @"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=|DataDirectory|MyDb.accdb;Persist Security Info=True";

    // Create your sql query in a string variable
    string cmdText = string.Format("INSERT INTO Customer(Name, Phone) VALUES('{0}','{1}');", name, phone);

    // Use the 'using' statement on your connection so that the resource is managed properly
    using (System.Data.OleDb.OleDbConnection connection = new System.Data.OleDb.OleDbConnection(connString))
    {                
        // Here's where/how we fire off the INSERT statement
        OleDbCommand cmd = new OleDbCommand(cmdText, connection);
        connection.Open();
        cmd.ExecuteNonQuery();
    }
}

如何正确初始化.NET OleDbConnection对象及其ConnectionString属性？

1 个答案: