I'm trying to get data from database according to the item selected in the ComboBox but when I try to access the selected ComboBox item it gives me "System.Data.DataRowView" [...?]

I did the same thing with a simple select query in another function and that works fine but I don't know why it doesn't work in this query:

_dataAdapter.SelectCommand.CommandText = "SELECT lt.Name FROM Leader as lt LEFT JOIN Material as mt ON lt.Student_id=mt.lead_id where lt.Name=" + "'" + cmbLeader.SelectedItem.ToString() + "'";

Can anybody tell me what might be the problem?

c# winforms combobox
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