Determine if Dataset is empty [C#]

[Shaitan00]

My goal - I need to search a database (EXCEL file) using typical "SELECT" statements (as shown below) to determine if a matching value exists (stored in the dataset).

If the Dataset (ds) is EMPTY or ==NULL then I need to do something specific... So I wrote the following code:

 

System.Data.DataSet dsChg = oExcel.Read("select * from [Task$] where STATUS<>'FINISHED' and CLIENTS='" + cbClient.Text + "' and ASSIGNMENTS='" + cbAssignment.Text + "'");
if (dsChg != null)
{	// Repopulate
	... do some work
}

Note that oExcel is an object that allows me to communicate with my EXCEL [.xls] file which is acting as a database.

So, I am checking to see if there is a row that has STATUS != FINISHED, and CLIENTS & ASSIGNMENTS = to the current values in the corresponding comboboxes

 

Problem I am having - even if I am 100% sure the Dataset is empty (meaning if I populate a datagrid with the Dataset there are no values/results) BUT the "if (dsChg != null) isn't working - the dataset is evaluated as if it wasn't empty.

This is causing me a lot of problems because if it is not empty than I assume that row(0) has values and when I try to access them I get errors because there is nothing in row(0) - shouldn't that mean the Dataset is EMPTY?

 

So I need a better/more accurate/correct way to determine if the Dataset is empty or not (meaning did it find a match in the Excel Database).

Any help/hints/comments would be much appreciated, Thanks

[bri189a]

A dataset has tables is in it - you need to check all the tables for no rows. Your sql just returns an empty cursor but still causes there to be a table. What you need to do is:

 

bool dsEmpty = true;
int tbCount = 0;

while(dsEmpty && tbCount < dsChg.Tables.Count)
{
   if(dsChg.Tables[tbCount].Rows.Count > 0)
      dsEmpty = false;
   else
      tbCount++;
}

//Now dsEmpty holds whether the ds is 'empty' or not.