I am having trouble with the formatting of SQL results, my code looks something like this:

mmDataSet ds = (mmDataSet)this.GetDataSet("SELECT " +
"dollarAmt FROM myTable);

this.dollarString = ds.Tables[0].Rows[0][0].ToString();

This works fine, but if I try to change to:

this.dollarString = ds.Tables[0].Rows[0][0].ToString("C");

I get the error:

No overload for method 'ToString' takes '1' arguments

How do I format the numeric value in the DataSet to display in currency format?

Kind Regards,

Mat