How to set dropdown width according to longest string in C#

If you are using window control then use this method.
private void AdjustWidthComboBox_DropDown(object sender, System.EventArgs e)
{
ComboBox senderComboBox = (ComboBox)sender;
int width = senderComboBox.DropDownWidth;
Graphics g = senderComboBox.CreateGraphics();
Font font = senderComboBox.Font;
int vertScrollBarWidth =
(senderComboBox.Items.Count>senderComboBox.MaxDropDownItems)
?SystemInformation.VerticalScrollBarWidth:0;

int newWidth;
foreach (string s in ((ComboBox)sender).Items)
{
newWidth = (int) g.MeasureString(s, font).Width
+ vertScrollBarWidth;
if (width < newWidth )
{
width = newWidth;
}
}
senderComboBox.DropDownWidth = width;
}

If you are a web developer then :-
Get the length of longest string and pass it in unit.pixel method like this :-
DropDownList1.Width = Unit.Pixel(LengthOfTheLongestString)

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