c# - Add an item to combobox before binding data from the database -

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i had combobox in windows forms form retrieves data database. did well, want add first item <-please select category-> before data database. how can that? , can put it?

public category() {     initializecomponent();     categoryparent();  }  private void categoryparent() {     using (sqlconnection con = getconnection())     {         sqldataadapter da = new sqldataadapter("select category.category, category.id category", con);         datatable dt = new datatable();         da.fill(dt);         cbparent.datasource = dt;         cbparent.displaymember = "category";         cbparent.valuemember = "id";     } }

you either add default text text property of combobox (preferred):

cbparent.text = "<-please select category->";

or, add value datatable directly:

da.fill(dt); datarow row = dt.newrow(); row["category"] = "<-please select category->"; dt.rows.insertat(row, 0); cbparent.datasource = dt;

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