```
<data>
<food>
<id>1</id>
<name>asparagus</name>
<catlog>7190</catlog>
</food>
<food>
<id>2</id>
<name>almonds</name>
<catlog>7190</catlog>
</food>
<food>
<id>3</id>
<name>asparagus</name>
<catlog>7192</catlog>
</food>
<food>
<id>4</id>
<name>asparagus</name>
<catlog>7193</catlog>
</food>
</data>

```

i would like to get the unique catlogs, so from this list i want to extract only 7190, 7192, and 7193. i have a script that puts it into a dropdownlist by using:

```
DropDownList1.DataSource = dv
        DropDownList1.DataBind()

```

but i need it to get only the unique values.