static internal void SetSelectedValue(System.Windows.Forms.ComboBox comboBox, SelectedItemOptions options = SelectedItemOptions.None, object valueToSelect = null, object valueForNull = null)
{
object selectedValue;
if (comboBox.Items.Count > 0)
{
selectedValue = comboBox.SelectedValue;
if (valueToSelect == null)
{
valueToSelect = valueForNull;
}
switch (options)
{
case SelectedItemOptions.None:
comboBox.SelectedIndex = -1;
break;
case SelectedItemOptions.First:
comboBox.SelectedIndex = 0;
break;
case SelectedItemOptions.NoneOrFirstIfUnique:
if (comboBox.Items.Count == 1)
{
comboBox.SelectedIndex = 0;
}
else
{
comboBox.SelectedIndex = -1;
}
break;
case SelectedItemOptions.Last:
comboBox.SelectedIndex = comboBox.Items.Count - 1;
break;
case SelectedItemOptions.Current:
comboBox.SelectedValue = selectedValue;
break;
case SelectedItemOptions.CurrentOrFirst:
comboBox.SelectedValue = selectedValue;
if (comboBox.SelectedValue == null)
{
comboBox.SelectedIndex = 0;
}
break;
case SelectedItemOptions.CurrentOrFirstIfUnique:
comboBox.SelectedValue = selectedValue;
if (comboBox.SelectedValue == null)
{
if (comboBox.Items.Count == 1)
{
comboBox.SelectedIndex = 0;
}
else
{
comboBox.SelectedIndex = -1;
}
}
break;
case SelectedItemOptions.CurrentOrLast:
comboBox.SelectedValue = selectedValue;
if (comboBox.SelectedValue == null)
{
comboBox.SelectedIndex = comboBox.Items.Count - 1;
}
break;
case SelectedItemOptions.Value:
if (valueToSelect == null)
{
comboBox.SelectedIndex = -1;
}
else
{
comboBox.SelectedValue = valueToSelect;
}
break;
case SelectedItemOptions.ValueOrFirst:
if (valueToSelect == null)
{
comboBox.SelectedIndex = 0;
}
else
{
comboBox.SelectedValue = valueToSelect;
if (comboBox.SelectedValue == null)
{
comboBox.SelectedIndex = 0;
}
}
break;
case SelectedItemOptions.ValueOrFirstIfUnique:
if (valueToSelect == null)
{
if (comboBox.Items.Count == 1)
{
comboBox.SelectedIndex = 0;
}
else
{
comboBox.SelectedIndex = -1;
}
}
else
{
comboBox.SelectedValue = valueToSelect;
if (comboBox.SelectedValue == null)
{
if (comboBox.Items.Count == 1)
{
comboBox.SelectedIndex = 0;
}
else
{
comboBox.SelectedIndex = -1;
}
}
}
break;
case SelectedItemOptions.ValueOrLast:
if (valueToSelect == null)
{
if (comboBox.SelectedValue == null)
{
comboBox.SelectedIndex = comboBox.Items.Count - 1;
}
}
else
{
comboBox.SelectedValue = valueToSelect;
if (comboBox.SelectedValue == null)
{
comboBox.SelectedIndex = comboBox.Items.Count - 1;
}
}
break;
default:
break;
}
}
}
static internal void SetItemByDisplayValue(System.Windows.Forms.ComboBox comboBox, string displayValue, SelectedItemOptions options = SelectedItemOptions.None)
{
if (comboBox.Items.Count == 0)
{
return;
}
int index = comboBox.FindStringExact(displayValue);
if (index == -1)
{
switch (options)
{
case SelectedItemOptions.None:
comboBox.SelectedIndex = -1;
break;
case SelectedItemOptions.First:
comboBox.SelectedIndex = 0;
break;
case SelectedItemOptions.NoneOrFirstIfUnique:
if (comboBox.Items.Count == 1)
{
comboBox.SelectedIndex = 0;
}
else
{
comboBox.SelectedIndex = -1;
}
break;
case SelectedItemOptions.Last:
comboBox.SelectedIndex = comboBox.Items.Count - 1;
break;
default:
break;
}
}
else
{
comboBox.SelectedIndex = index;
}
}
