How to SELECT a dropdown list item by value programmatically

Question

How to SELECT a drop down list item by value programatically in C#.NET?

Answer 1

combobox1.SelectedValue = x;

I suspect you may want yo hear something else, but this is what you asked for.

Answer 2

ddl.SetSelectedValue("2");

With a handy extension:

public static class WebExtensions
{

    /// <summary>
    /// Selects the item in the list control that contains the specified value, if it exists.
    /// </summary>
    /// <param name="dropDownList"></param>
    /// <param name="selectedValue">The value of the item in the list control to select</param>
    /// <returns>Returns true if the value exists in the list control, false otherwise</returns>
    public static Boolean SetSelectedValue(this DropDownList dropDownList, String selectedValue)
    {
        ListItem selectedListItem = dropDownList.Items.FindByValue(selectedValue);

        if (selectedListItem != null)
        {
            selectedListItem.Selected = true;
            return true;
        }
        else
            return false;
    }
}

Note: Any code is released into the public domain. No attribution required.

Answer 3

Ian Boyd (above) had a great answer -- Add this to Ian Boyd's class "WebExtensions" to select an item in a dropdownlist based on text:

/// <summary>
/// Selects the item in the list control that contains the specified text, if it exists.
/// </summary>
/// <param name="dropDownList"></param>
/// <param name="selectedText">The text of the item in the list control to select</param>
/// <returns>Returns true if the value exists in the list control, false otherwise</returns>
public static Boolean SetSelectedText(this DropDownList dropDownList, String selectedText)
{
    ListItem selectedListItem = dropDownList.Items.FindByText(selectedText);
    if (selectedListItem != null)
    {
        selectedListItem.Selected = true;
        return true;
    }
    else
        return false;
}

To call it:

WebExtensions.SetSelectedText(MyDropDownList, "MyValue");

Answer 4

If you know that the dropdownlist contains the value you're looking to select, use:

ddl.SelectedValue = "2";

If you're not sure if the value exists, use (or you'll get a null reference exception):

ListItem selectedListItem = ddl.Items.FindByValue("2");

if (selectedListItem != null)
{
    selectedListItem.Selected = true;
}

Answer 5

ddlPageSize.Items.FindByValue("25").Selected = true;

Answer 6

I prefer

if(ddl.Items.FindByValue(string) != null)
{
    ddl.Items.FindByValue(string).Selected = true;
}

Replace ddl with the dropdownlist ID and string with your string variable name or value.