Calling Class in C#

Question

I am developing a series of processes in C# which reuse the same SQL code. Below is an example of a Class I created for the SQL Connection to my test database. Question: how to do I call the Class in my process? I have tried a couple of things however, I get the below errors

Errors:

SQLHelperCode.FirstConnect is a 'type'  which is not valid in the given context.
Only Assignment, call, increment, decrement and new object expressions can be used as a statement

Class FirstConnect

public class FirstConnect
{
    public FirstConnect()
    {
        SqlConnection conn;
        string path = @"C:\Program Files (x86)\Microsoft SQL Server\MSSQL.1\MSSQL\Data";
        const string dbName = "datadetail";
        {
            conn = new SqlConnection("user id=TestUser;" +
                                     "server=TestData\\SQLEXPRESS;" +
                                     "Trusted_Connection=yes;" +
                                     "connection timeout=30");

            try
            {
                conn.Open();
            }
            catch (Exception e)
            {
                Console.WriteLine(e.ToString());
            }
        }
    }
}

Want to call the FirstConnect in this code:

protected override void OnBarUpdate()
{
    accountName = Account.Name.ToString();

    if (accountName == 'Test1234')
    {
        //Call FirstConnect here.
    }
}

Instantiate the class and invoke the method like so: FirstConnect myThing = new FirstConnect(); myThing.DoSomething. The code you have provided above does not have a method on the class to call. — Kell
– Kell, Commented May 25, 2012 at 17:00
replace //Call FirstConnect here. with new FirstConnect(); And make sure you close your connection — prashanth
– prashanth, Commented May 25, 2012 at 19:12

Conrad Frix · Accepted Answer · 2012-05-25 17:01:56Z

5

This line defines the class

public class FirstConnect
 {

This line defines the constuctor

    public FirstConnect()
      {

The following will define a variable of type FirstConnect and then call the constructor to create it (I made it two lines to be explicit)

FirstConnect fc;
fc  = new FirstConnect();

Typically you'd then want to have method that actually does something with the object

e.g.

SomeOtherObject varaibleName = fc.GetSomeData(accountName);

answered May 25, 2012 at 17:01

Conrad Frix

52.8k13 gold badges100 silver badges158 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

Adam Sweeney · Accepted Answer · 2012-05-25 17:00:50Z

1

FirstConnect fc = new FirstConnect();

answered May 25, 2012 at 17:00

Adam Sweeney

3863 silver badges15 bronze badges

Comments

Austin Salonen · Accepted Answer · 2012-05-25 17:07:37Z

1

Not an answer but just a large comment...

When using classes that implement IDisposable like SqlConnection does, they should be used like so:

using (var conn = new SqlConnection("user id=TestUser;server=TestData\\SQLEXPRESS;Trusted_Connection=yes;connection timeout=30"))
{
   //... do work ... 
}

answered May 25, 2012 at 17:07

community wiki

Austin Salonen

1 Comment

Conrad Frix Over a year ago

What you wrote is true but doesn't apply here. conn is a field on FirstConnect so the scope of conn can't be constrained to a using block. So FirstConnect should either implement IDisposable or be refactored so that it has connectionString field that gets used as you suggest in each method that uses it.

Collectives™ on Stack Overflow

Calling Class in C#

3 Answers 3

Comments

Comments

1 Comment

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

Comments

Comments

1 Comment

Your Answer

Sign up or log in

Post as a guest

Related