Using select count(*) in c#

Question

    String dd_webCofig = ConfigurationManager.ConnectionStrings["server132"].ConnectionString;
    SqlConnection ddlistconn = new SqlConnection(dd_webCofig);
    ddlistconn.Open();

    string ddlist = "select count(*) from jud_order where complex_name=@a and case_no=@b and sign=@c and jud_order_date=@d and user_code=@e";
    SqlCommand ddlistCmd = new SqlCommand(ddlist, ddlistconn);
    ddlistCmd.Parameters.AddWithValue("a", "a");
    ddlistCmd.Parameters.AddWithValue("b", "a");
    ddlistCmd.Parameters.AddWithValue("c", "a");
    ddlistCmd.Parameters.AddWithValue("d", "a");
    ddlistCmd.Parameters.AddWithValue("e", "a");

    SqlDataReader myReader = ddlistCmd.ExecuteReader();

I am having the above query which returns number of rows, now my problem is how t read the output of the query? What i want is

 if(count=0)
{ 
   //Do
} 
else if(counnt >0)
{
    //Do something else
}

m.edmondson · Accepted Answer · 2011-04-18T11:13:50.863

13

You want to use ExecuteScalar(); instead which will return a single result.

So this line:

ddlistCmd.ExecuteReader();

should be:

ddlistCmd.ExecuteScalar();

which you can then assign to count after type casting the result.

edited Apr 18 '11 at 11:13

answered Apr 18 '11 at 11:04

m.edmondson

29,632
26
117
199

1

Note that ExecuteScalar returns object. You will need to cast the result to int. – Artemix Apr 18 '11 at 11:10
And you have to type-cast the result. – Henk Holterman Apr 18 '11 at 11:10
His problem is, how to read the output of the query. How does this have so many up votes without the answer? – clamchoda Apr 19 '11 at 14:33
@Chris - This is the answer - surely? – m.edmondson Apr 19 '11 at 14:35
Can you make an edit showing how to access the count(*) stored in the ddListCmd? I think he will accept your answer after that! – clamchoda Apr 19 '11 at 14:37
My answer already fully answers that `SqlCommand ddlistCmd` contains the result of the query which is then accessed by looking at `count`. So `count = ddlistCmd.ExecuteScalar()` – m.edmondson Apr 19 '11 at 14:48

score 0 · Answer 2 · edited Apr 18 '11 at 11:08

0

int result=ddlistCmd.ExecuteScalar();

edited Apr 18 '11 at 11:08

Oleks

31,334
11
76
131

answered Apr 18 '11 at 11:06

Zo Has

12,193
21
81
147

score -2 · Answer 3 · edited Apr 18 '11 at 11:08

-2

Try:

myReader.Read();
count= int.Parse(myReader[0].ToString());

edited Apr 18 '11 at 11:08

Oleks

31,334
11
76
131

answered Apr 18 '11 at 11:07

Varun Goel

319
3
15

RTFM ;) for exactly THIS there is a better wy (ExecuteScalar) – TomTom Apr 18 '11 at 11:10

Using select count(*) in c#

3 Answers3

Linked