combobox syntax

Question

I am getting an error like Syntax error (comma) in query expression 'marks,chaptername='2''Electromagnetic Induction''.

what query i should write to select from both combomarks and combochapters and display the set of questions the particular chapters accoding to the marks selected in c#?

private void comboBox1_SelectedIndexChanged(object sender, EventArgs e)

{

checkedListBox2.Items.Clear();

//cmbosubject.Items.Clear();

OleDbConnection con = new OleDbConnection(@"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + Application.StartupPath + "\\easyexamdb.mdb");

con.Open();

str = "select * from tblmcq where marks,chaptername='" + comboBox1.Text + "''" + checkedListBox1.SelectedItem + "'";

com = new OleDbCommand(str, con);

OleDbDataReader reader = com.ExecuteReader();

while (reader.Read())

{

checkedListBox2.Items.Add(reader["question"]); //.ToString());

}

con.Close();

reader.Close();
}

Vulpes · Answer

You need to use the 'and' operator between each condition that needs too be true in the where clause. You can't use a comma: str = select * from tblchapter where branch=' + cmbobranch.Text.Trim() + ' and subjectname=' + cmbosubject.Text.Trim() + 'and class_standard=' + cmboclass.Text.Trim()+';

Vulpes · Answer

If marks is a numeric field in the database try: str = select * from tblmcq where marks =  + comboBox1.Text +  and chaptername = ' + checkedListBox1.SelectedItem + '; but if it's a character field try: str = select * from tblmcq where marks = ' + comboBox1.Text + ' and chaptername = ' + checkedListBox1.SelectedItem + ';

rashmi kc · Answer

Ya its working :0

rashmi kc · Answer

Its working if i select for 2 combobox suppose if i select from three combobox again m getting error Syntax error (comma) in query expression 'branch='Prose'subjectname='English'and class_standard='10th''. how to write the query here s my code str = select * from tblchapter where branch=' + cmbobranch.Text.Trim() + 'subjectname=' + cmbosubject.Text.Trim() + 'and class_standard=' + cmboclass.Text.Trim()+';