Question

I am developing an asp.net application and I got stuck, so I am asking for some help.

Database: In my database (MySql) I have table ingredient(idI, name, etc.) and each ingredient can have more then one ingredient type(idT, type_name, etc.). Because of many to many relation I have another table which contains id from ingredient and id from ingredient type.

App: In my app I have gridview that shows all the data from ingredient. I use my own method called FillGVIngredient to fill gridview using dataset and data adapter.

Question: How can I display another column in my gridView which will show all the ingredient types that belongs to ingredient id (each row in gridview represents 1 ingredient) with bullet list so that the output will look like this:

Ingredient_Type      Ingredient   id
--------------------------------------
-type 1*             ingredient1   1
-type 2*
-type 3*
--------------------------------------
-type 5              ingredient2   2
-type 6

*ingredient types must be displayed in single cell. Example above shows 2 rows from gridview.

I have tried using template field with bullet list but I don’t know how to iterate through rows so that I would pass the id of ingredient to sql statement of bullet list datasource.

Answer 1

You are on the right track. A BulletedList in a TemplateField is the correct approach. But you should use GridView’s RowDataBound to bind it to it’s DataSource. Have a look:

protected void GridView1_RowDataBound(Object sender, GridViewRowEventArgs e)
{
    if(e.Row.RowType == DataControlRowType.DataRow) {
        var rowView = (DataRowView)e.Row.DataItem;
        var bullet = (BulletedList)e.Row.FindControl("BulletedList1");
        // now get the DataSource according to the ID (f.e. rowView["Ingredient_ID"]) 
        bullet.DataSource = getIngredientTypes(rowView["Ingredient_ID"]);
        bullet.DataTextField = "Ingredient_Type";
        bullet.DataValueField = "Type_ID";
        bullet.DataBind();
    }
}