Hi all,

I have a combo box that is bound to a database table.
How do i restrict the items displayed to the user; for example, i do not want to display names that containthe character "%" in c#

thanks

Hi omogen,

ComboBox’s items cannot be added or removed once it is data bound. Do the filter in the data source is a proper way. Please look at the following code.
dtComboBox.Columns.Add("Name");
dtComboBox.Columns.Add("Show");
dtComboBox.Rows.Add("John", true);
dtComboBox.Rows.Add("Mike", true);
dtComboBox.Rows.Add("%Kira", true);

foreach (DataRow dr in dtComboBox.Rows)
{
if (dr["Name"].ToString().Contains('%'))
{
dr["Show"] = false;
}
}

dtComboBox.DefaultView.RowFilter = "Show=true";

comboBox1.DataSource = dtComboBox;
comboBox1.DisplayMember = "Name";
dtComboBox is a datatable which will be used to do the databinding. In the example, I have added a column called “Show� At first, all the rows�Show value is set to true. Then put a loop to check if the name contains �� Set Show to false for the row whose name contains �� After that, you can use RowFilter to show the rows whose “Show�value is true.

If you have any problems with my solution, please feel free to tell me.

Sincerely,
Kira Qian

---

Please remember to mark the replies as answers if they help and unmark them if they provide no help.
Welcome to the All-In-One Code Framework!

Hi Omogen,

1. Put the result set of your query into a DataTable

dim myDataTable = <your query>

2. Change the DefaultView of your DataTable. That is to exclude those items you dont need

myDataTable.DefaultView.RowFilter = <your filter criteria>

3. Then assign your DataTable as the Datasource of your comboBox

myComboBox.DataSource = myDataTable

Hope this will work...

Why not just update the SQL Select query that pulls the list to filter out those?

---

MCP

Hi omogen,

ComboBox’s items cannot be added or removed once it is data bound. Do the filter in the data source is a proper way. Please look at the following code.
dtComboBox.Columns.Add("Name");
dtComboBox.Columns.Add("Show");
dtComboBox.Rows.Add("John", true);
dtComboBox.Rows.Add("Mike", true);
dtComboBox.Rows.Add("%Kira", true);

foreach (DataRow dr in dtComboBox.Rows)
{
if (dr["Name"].ToString().Contains('%'))
{
dr["Show"] = false;
}
}

dtComboBox.DefaultView.RowFilter = "Show=true";

comboBox1.DataSource = dtComboBox;
comboBox1.DisplayMember = "Name";
dtComboBox is a datatable which will be used to do the databinding. In the example, I have added a column called “Show� At first, all the rows�Show value is set to true. Then put a loop to check if the name contains �� Set Show to false for the row whose name contains �� After that, you can use RowFilter to show the rows whose “Show�value is true.

If you have any problems with my solution, please feel free to tell me.

Sincerely,
Kira Qian

---

Please remember to mark the replies as answers if they help and unmark them if they provide no help.
Welcome to the All-In-One Code Framework!

Hi Omogen,

1. Put the result set of your query into a DataTable

dim myDataTable = <your query>

2. Change the DefaultView of your DataTable. That is to exclude those items you dont need

myDataTable.DefaultView.RowFilter = <your filter criteria>

3. Then assign your DataTable as the Datasource of your comboBox

myComboBox.DataSource = myDataTable

Hope this will work...