You cant use foreach
here because you change the listBox1.Items
inside the loop,
Use while loop and check the listBox1.Items.Count() >0
and inside the loop you can pic first item and move it to second one or remove.
while (ListBox1.Items.Count>0)
{
var item = ListBox1.Items[0].ToString();
using (OracleCommand crtCommand = new OracleCommand("select count(*) from(( select * from all_ind_columns where index_name= '" + item + "' and table_owner='" + txtSrcUserID.Text.ToUpper() + "'))", conn1))
using (OracleCommand ctCommand = new OracleCommand("select count(*) from(( select * from all_ind_columns where index_name= '" + item + "' and table_owner='" + txtDesUserID.Text.ToUpper() + "'))", conn1))
{
string result1 = crtCommand.ExecuteScalar().ToString();
string result2 = ctCommand.ExecuteScalar().ToString();
if (result1 != result2)
{
ListBox2.Items.Add(item);
}
ListBox1.Items.RemoveAt(0);
}
}
Note: your code is open for sql injection attacks, use parameters instead of inline parameters.
while (ListBox1.Items.Count>0)
{
var item = ListBox1.Items[0].ToString();
using (OracleConnection con = new OracleConnection(connectionString))
using (OracleCommand cmd = con.CreateCommand())
{
con.Open();
cmd.CommandText = "select count(*) from(( select * from all_ind_columns where index_name= :item and table_owner=:table_owner))";
cmd.Parameters.Add(item);
cmd.Parameters.Add(txtSrcUserID.Text.ToUpper());
string result1 = cmd.ExecuteScalar().ToString();
cmd.Parameters.Clear();
cmd.Parameters.Add(item);
cmd.Parameters.Add(txtDesUserID.Text.ToUpper());
string result2 = cmd.ExecuteScalar().ToString();
if (result1 != result2)
{
ListBox2.Items.Add(item);
}
ListBox1.Items.RemoveAt(0);
}
}