SqlDataReader Class does not have any Constructor ?

Question

0.00/5 (No votes)

See more:

Q) I heard in some video that 'SqlDataReader' class does not have any constructor. Is it true ?
As far as my knowledge there is no class can have zero constructors. If I don not write
declare any constructor in a class then C# compiler will add default constructor to the class.

Q)If my Code is like
SqlDataReader dr;
Some people are saying that dr is object.
Is it a Object or Reference Variable ?

Posted 30-Jul-14 20:33pm

Sandeep Reddy Badikolu

Add a Solution

2 solutions

Solution 1

You can check MSDN documentation - http://msdn.microsoft.com/en-us/library/system.data.sqlclient.sqldatareader%28v=vs.110%29.aspx[^].
According to this - "To create a SqlDataReader, you must call the ExecuteReader method of the SqlCommand object, instead of directly using a constructor."

dr is a variable that holds a pointer to an object.
A ref is different - http://msdn.microsoft.com/en-us/library/14akc2c7.aspx[^].

Posted 30-Jul-14 20:49pm

Abhinav S

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

CPallini · Accepted Answer · 2014-07-30T20:52:00

1. The constructor is not exposed, that is not publicly available:

To create a SqlDataReader, you must call the ExecuteReader method of the SqlCommand object, instead of directly using a constructor.

2. dr is a reference variable. After the

SqlDatareader dr

statement, dr is equal to null.