sql query from combobox's and textbox , help please

Question

my fist question here , am 1 year experience in c# sql >> the point is i have table named : Pa_Info

when i select data from combo box's i need it to display to DataGrid view , if i didn't type in text box , bring the rest needed data

help please , thanks in advance

Answer 1

Best recommendation is to use the builder pattern as done with the NuGet package SqlKata with documentation here.

Simple select code sample getting data from two ComboBox controls SELECT * FROM [Contacts] WHERE [FirstName] = @p0 AND [LastName] = @p1

using var cn = new SqlConnection("Data Source=.\\sqlexpress;Initial Catalog=NorthWind2020;Integrated Security=True");  
SqlServerCompiler compiler = new ();  
  
var db = new QueryFactory(cn, compiler);  
  
var query = db.Query("Contacts");  
  
// add first condition  
query = query.Where("FirstName", ContactFirstNameComboBox.Text);  
  
// add another condition  
query = query.Where("LastName", ContactLastNameComboBox.Text);  
SqlResult result = compiler.Compile(query);  
  
// this is the SQL statement parameterized  
string sql = result.Sql;