/// <summary>
/// actual execute of the database query
/// simple query which selects all the students that their last name or first name contains the string parameter (searchString)
/// </summary>
/// <param name="searchString">string parameter</param>
/// <returns></returns>
public IEnumerable <tbl_StudentsList> GetSearchString(string searchString)
{
tbl_StudentsList[] res;
// returns an empty array if the length of the string parameter length is smaller than 2. insure that there will be no access to database in this case.
if (searchString.Length < 2)
{
return(new tbl_StudentsList[0]);
}
try
{
// run query through entity framework
using (var context = new SchoolDataBaseEntities())
{
var blog = from el in context.tbl_StudentsList
where el.FirstName.IndexOf(searchString) >= 0 || el.LastName.IndexOf(searchString) >= 0
select el;
res = blog.ToArray();
}
}
catch (Exception ex)
{
// in case of error returns an empty string and write error in the Event Viewer.
res = new tbl_StudentsList[0];
using (EventLog eventLog = new EventLog("Application"))
{
eventLog.Source = "Application";
eventLog.WriteEntry("Error In School Application:\n" + ex.Message + "\n" + ex.StackTrace, EventLogEntryType.Error, 101, 1);
}
}
return(res);
}