'ExecuteNonQuery: Connection property has not been initialized.'

Question

我搜索了这个论坛，并尝试了很多我找到的可能的解决方案，但没有任何效果。任何人都可以阐明这种情况吗？谢谢！

SqlConnection con = new SqlConnection(@"Data Source=.\sqlexpress;Initial Catalog=TESTdatabase;Integrated Security=True");
con.Open();

SqlCommand cmd = new SqlCommand(
  "INSERT into tblGenerator (GeneratorName, GeneratorAddress, GeneratorCity, GeneratorState, GeneratorZip, GeneratorPhone, GeneratorContact, GeneratorEPAID) " +
  "VALUES ('" + GenName.Text + "' , '" + GenAdd.Text + "' , '" + GenCity.Text + "' , '" + GenState.Text + "' , '" + GenZip.Text + "' , '" + GenPhone.Text + "' ," +
 " '" + GenContact.Text + "' , '" + GenEPAID.Text + "' ), con");

cmd.ExecuteNonQuery();
con.Close();

Answer 1

看起来您在创建 SqlCommand 时，将连接作为 Insert 语句的一部分。具体来说，“, con”仍然包含在您的文本字符串中。如果您将最后一个双引号移到括号之后，它应该可以工作。

但是，我建议您像这样重写您的代码：

using (var con = new SqlConnection(@"Data Source=.\sqlexpress;Initial Catalog=TESTdatabase;Integrated Security=True"))
{
    if(ConnectionState.Closed == con.State) con.Open();
    using (var cmd = con.CreateCommand())
    {
        cmd.CommandType = CommandType.Text;
        cmd.CommandText = $@"INSERT INTO tblGenerator (GeneratorName, GeneratorAddress, GeneratorCity, GeneratorState, GeneratorZip, GeneratorPhone, GeneratorContact, GeneratorEPAID)
                            VALUES ('{GenName.Text}', '{GenAdd.Text}', '{GenCity.Text}', '{GenState.Text}', '{GenZip.Text}', '{GenPhone.Text}', '{GenContact.Text}', '{GenEPAID.Text}')";
        cmd.ExecuteNonQuery();
    }
}

Answer 2

这是我最终使用的代码。谢谢大家的帮助。

        SqlConnection myConnection =
            new SqlConnection(@"Data Source=.\sqlexpress;Initial Catalog=TESTdatabase;Integrated Security=True");

        SqlCommand myCommand = new SqlCommand(
            "INSERT into tblGenerator (GeneratorName, GeneratorAddress, GeneratorCity, GeneratorState, GeneratorZip, GeneratorPhone, GeneratorContact, GeneratorEPAID)" +
            "VALUES (@GenName, @GenAdd, @GenCity, @GenState, @GenZip, @GenPhone, @GenContact, @GenEPAID)");
        myCommand.Parameters.AddWithValue("@GenName", GenName.Text);
        myCommand.Parameters.AddWithValue("@GenAdd", GenAdd.Text);
        myCommand.Parameters.AddWithValue("@GenCity", GenCity.Text);
        myCommand.Parameters.AddWithValue("@GenState", GenState.Text);
        myCommand.Parameters.AddWithValue("@GenZip", GenZip.Text);
        myCommand.Parameters.AddWithValue("@GenPhone", GenPhone.Text);
        myCommand.Parameters.AddWithValue("@GenContact", GenContact.Text);
        myCommand.Parameters.AddWithValue("@GenEPAID", GenEPAID.Text);



        myConnection.Open();
        myCommand.Connection = myConnection;
        MessageBox.Show("You Have Successfully Added a New Generator To SQL");
        myCommand.ExecuteNonQuery();
        myConnection.Close();

'ExecuteNonQuery: Connection property has not been initialized.'

'ExecuteNonQuery: Connection property has not been initialized.'

c#

sql

ado.net

sqlcommand