Re: How to store the retrieved values from a coulmn of a table in an array?? - C# Discussion Boards

Re: How to store the retrieved values from a coulmn of a table in an array??

9-Aug-07 21:41

Hi All,
PLease let me know if how can a save the values in a column from a database in an array using C# .NET Web Application (so that i could use each value in the array in my code one by one.)
For Eg.: if i have the following query:

SELECT Name FROM Details WHERE Country='India'
here "Name" and "Country" are two columns in table called "Details".

Suppose the query returns Three values: Ram, John and Sohail
i want these names to be saved in an arraay.

i could not use the "ExecuteScalar" class as it can save only one value into a variable!

please send me the few lines of code necessary to do that using the above mentioned example.

Thanks,
Ramesh

Talal Sultan9-Aug-07 21:55

Re: How to store the retrieved values from a coulmn of a table in an array??

9-Aug-07 21:55

The SELECT command will already return the values in a table format. You need a data reader to loop through the values. You have to create your own DataTable (in this case with one column) and insert the values as you loop the data reader. If you are using SQL Server, you can use the SqlDataReader class.

Assuming you have:

sql command: SqlCommand myCommand = new SqlCommand();
data table: DataTable myTable = new DataTable();

You would have to put something like this

SqlDataReader dr = myCommand.ExecuteReader();

while (dr.Read()) // reads as long as there are values 
{
  DataRow row = myTable.NewRow();
  row[0] = dr.GetString(0); // to get the Name column
  row[1] = ...... // if you have other columns
  myTable.Rows.Add(row);
}
dr.Close();

Good luck

Talal

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Giorgi Dalakishvili9-Aug-07 22:03

Giorgi Dalakishvili

9-Aug-07 22:03

Instead of manually adding each row to the datatable you can use dataadapter to fetch all the values

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Re: How to store the retrieved values from a coulmn of a table in an array??

rameshbhojan10-Aug-07 0:42

Re: How to store the retrieved values from a coulmn of a table in an array??

10-Aug-07 0:42

Thanks Talal Smile | :)

Now how do i get these values from row and save in a array variable, which i need to pass as a parameter to a method???

Talal Sultan10-Aug-07 2:10

Re: How to store the retrieved values from a coulmn of a table in an array??

10-Aug-07 2:10

Like I said in my second post here http://www.codeproject.com/script/comments/forums.asp?msg=2176578&forumid=1649#xx2176578xx[^], you need to replace the data table stuff with the array stuff. Since you only return one column from the database, you would only need column 0 of the data reader:

ArrayList myList = new ArrayList();
SqlDataReader dr = myCommand.ExecuteReader();
while (dr.Read()) // reads as long as there are values 
    myList.Add(dr.GetString(0)); // to get the Name column  
dr.Close();

If your method has an Array parameter, you can convert ArrayList into Array as follows:

Array myArray = myList.ToArray();

rameshbhojan19-Aug-07 22:58

Re: How to store the retrieved values from a coulmn of a table in an array??

19-Aug-07 22:58

Thanks talal Smile | :)

Now if i wanna display all these values in the array(or datareader) in a dropdown list.... how do i do that???????

Talal Sultan19-Aug-07 23:21

Re: How to store the retrieved values from a coulmn of a table in an array??

19-Aug-07 23:21

You need to do a databinding.

If you have your data in the datatable as I first described, you would do as follows.

Supposing DataTable myTable = new DataTable(); is your table where the values are stored and DropDownList ddlFoo; is your drop down list, you would bind like this:

ddlFoo.DataSource = myTable;
ddlFoo.DataTextField = "ColumnNameForText";
ddlFoo.DataValueField = "ColumnNameForValue";
ddlFoo.DataBind();

Remember that you can only bind 2 columns of the table, one column should contain the text to be displayed in the DDL and one column should contain the corresponding value for each entry.

If you are using the ArrayList as I described ArrayList myList = new ArrayList(); you need to make sure that the object that you added in the array has 2 fields where you would place the text and the value fields. I use System.Web.UI.WebControls.ListItem because this class has 2 properties Text and Value. You would then make the binding in the same way you would do for the data table:

ddlFoo.DataSource = myList;
ddlFoo.DataTextField = "Text";
ddlFoo.DataValueField = "Value";
ddlFoo.DataBind();

Here we put Text and Value because these are the names of the properties of the ListItem class, but if you used another class with other fields, you would put their name here.

Hope this helps.

Talal

Giorgi Dalakishvili9-Aug-07 21:56

Giorgi Dalakishvili

9-Aug-07 21:56

You can use executereader, read all the values and store them in array but in my opinion arraylist would be better as you don't know how many values you'll need to store. But why do you need it? You can store values in datatable and then access them very easily.

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Re: How to store the retrieved values from a coulmn of a table in an array??

rameshbhojan19-Aug-07 21:19

Re: How to store the retrieved values from a coulmn of a table in an array??

19-Aug-07 21:19

Could you please give me a sample code(using my example above) to do the same as u mentioned.......

Giorgi Dalakishvili19-Aug-07 21:22

Giorgi Dalakishvili

19-Aug-07 21:22

http://www.codeproject.com/cs/database/DatabaseAcessWithAdoNet1.asp

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Re: How to store the retrieved values from a coulmn of a table in an array??

Talal Sultan9-Aug-07 21:57

Re: What to choose asp.net!!1

9-Aug-07 21:57

oops, I just noticed that you wanted the results in an Array. Well instead of a data table, you can use an ArrayList and add the elements as you read them from the data reader.

Talal

listview in c#

monuSaini9-Aug-07 21:34

monuSaini

9-Aug-07 21:34

Hello friends,

Can we set the no of rows in listview.

Regards,

rahul saini

Re: listview in c#

mav.northwind10-Aug-07 12:31

mav.northwind

10-Aug-07 12:31

Hi!
The number of rows simply is equal to the number of ListViewItems that have been added to the LV.

Regards,
mav

--
Black holes are the places where God divided by 0...

Albu Marius9-Aug-07 21:33

Albu Marius

9-Aug-07 21:33

In this community a post written in SMSscript is not appreciated and most likely will not get an answer concerning the problem. I suggest to write in plain English so that anyone can understand and reply to help you.

I am fighting against the Universe...
Reference-Rick Cook

Re: What to choose asp.net!!1

monuSaini9-Aug-07 23:23

monuSaini

9-Aug-07 23:23

Hello friend,

Can we set the no of rows in listview.

Regards,

rahul saini

Capturing Complete Webpage as an Image

Dinesh N Samarathunga9-Aug-07 20:29

Dinesh N Samarathunga

9-Aug-07 20:29

Hi Friends,

I try to capture whole web page opened with internet explorer as a image. I saw
the following project (http://www.codeproject.com/cs/media/IECapture.asp) But there are some problems with it.

Does any body has has done similar things.

Thanks In advance

Dinesh

Michael Sync9-Aug-07 20:35

Michael Sync

9-Aug-07 20:35

Dinesh N Samarathunga wrote:
there are some problems with it.

Maybe. you can tell us what problems you are having. maybe. we can help you..

Dinesh N Samarathunga wrote:
Does any body has has done similar things.

I found one here. "Web Capture[^]"

Thanks and Regards,
Michael Sync ( Blog: http://michaelsync.net)

If you want to thank me for my help, please vote my message by clicking one of numbers beside "Rate this message". Why vote? Plz Read it here. Thank you.

Dinesh N Samarathunga9-Aug-07 22:31

Dinesh N Samarathunga

9-Aug-07 22:31

Thanks Michael,

I saw your link. It works fine. But it also done with a web controller. Actually I need to capture the image of current (top IE window) IE Instance.

Thanks

Dinesh

Jax_qqq9-Aug-07 21:18

Jax_qqq

9-Aug-07 21:18

Dinesh, I have used the same code from code project only and it’s working just fine for me...
So please specify where exactly u r facing problem...

~Anuj~