How to select only one value in the ComboxBox List

I have a ComboBox which has 3 values

such as - NewYork,NewJersey,Boston.

Combobox.selectedIndex = 1  which is Boston,

On one scenario, i need to set only for Boston. I believe we can do it by ReadOnly or something like that.

I dont want to go for Enable = True / False. How to set this ?
Who is Participating?
I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

AndyAinscowFreelance programmer / ConsultantCommented:
Comboboxs don't have a readonly property.
Either disable it or remove the unwanted selection possibilities (ie. it only has Boston in the list part)
chokkaStudentAuthor Commented:
can you please share me the sample syntax, please
Here is an example:

Form1.cs -
using System.Collections.Generic;
using System.Windows.Forms;
using System.Linq;

namespace EE_Q28620474
	public partial class Form1 : Form
		private List<string> cities = new List<string>() { "New York", "New Jersey", "Boston" };

		public Form1()

		private void OnLoad(object sender, System.EventArgs e)
			cmbAll.DataSource = cities;
			cmbBOS.DataSource = (from city in cities where city.Equals("Boston") select city).ToList();
			cmbNY.DataSource = (from city in cities where city.Equals("New York") select city).ToList();
			cmbNJ.DataSource = (from city in cities where city.Equals("New Jersey") select city).ToList();

Open in new window

Form1.Designer.cs -
namespace EE_Q28620474
	partial class Form1
		/// <summary>
		/// Required designer variable.
		/// </summary>
		private System.ComponentModel.IContainer components = null;

		/// <summary>
		/// Clean up any resources being used.
		/// </summary>
		/// <param name="disposing">true if managed resources should be disposed; otherwise, false.</param>
		protected override void Dispose(bool disposing)
			if (disposing && (components != null))

		#region Windows Form Designer generated code

		/// <summary>
		/// Required method for Designer support - do not modify
		/// the contents of this method with the code editor.
		/// </summary>
		private void InitializeComponent()
			this.lblAll = new System.Windows.Forms.Label();
			this.cmbAll = new System.Windows.Forms.ComboBox();
			this.lblNewYork = new System.Windows.Forms.Label();
			this.cmbNY = new System.Windows.Forms.ComboBox();
			this.lblNewJersey = new System.Windows.Forms.Label();
			this.cmbNJ = new System.Windows.Forms.ComboBox();
			this.lblBoston = new System.Windows.Forms.Label();
			this.cmbBOS = new System.Windows.Forms.ComboBox();
			// lblAll
			this.lblAll.AutoSize = true;
			this.lblAll.Location = new System.Drawing.Point(12, 9);
			this.lblAll.Name = "lblAll";
			this.lblAll.Size = new System.Drawing.Size(49, 13);
			this.lblAll.TabIndex = 3;
			this.lblAll.Text = "All Items:";
			// cmbAll
			this.cmbAll.FormattingEnabled = true;
			this.cmbAll.Location = new System.Drawing.Point(14, 25);
			this.cmbAll.Name = "cmbAll";
			this.cmbAll.Size = new System.Drawing.Size(121, 21);
			this.cmbAll.TabIndex = 2;
			// lblNewYork
			this.lblNewYork.AutoSize = true;
			this.lblNewYork.Location = new System.Drawing.Point(141, 9);
			this.lblNewYork.Name = "lblNewYork";
			this.lblNewYork.Size = new System.Drawing.Size(57, 13);
			this.lblNewYork.TabIndex = 5;
			this.lblNewYork.Text = "New York:";
			// cmbNY
			this.cmbNY.FormattingEnabled = true;
			this.cmbNY.Location = new System.Drawing.Point(143, 25);
			this.cmbNY.Name = "cmbNY";
			this.cmbNY.Size = new System.Drawing.Size(121, 21);
			this.cmbNY.TabIndex = 4;
			// lblNewJersey
			this.lblNewJersey.AutoSize = true;
			this.lblNewJersey.Location = new System.Drawing.Point(270, 9);
			this.lblNewJersey.Name = "lblNewJersey";
			this.lblNewJersey.Size = new System.Drawing.Size(65, 13);
			this.lblNewJersey.TabIndex = 7;
			this.lblNewJersey.Text = "New Jersey:";
			// cmbNJ
			this.cmbNJ.FormattingEnabled = true;
			this.cmbNJ.Location = new System.Drawing.Point(272, 25);
			this.cmbNJ.Name = "cmbNJ";
			this.cmbNJ.Size = new System.Drawing.Size(121, 21);
			this.cmbNJ.TabIndex = 6;
			// lblBoston
			this.lblBoston.AutoSize = true;
			this.lblBoston.Location = new System.Drawing.Point(399, 9);
			this.lblBoston.Name = "lblBoston";
			this.lblBoston.Size = new System.Drawing.Size(43, 13);
			this.lblBoston.TabIndex = 9;
			this.lblBoston.Text = "Boston:";
			// cmbBOS
			this.cmbBOS.FormattingEnabled = true;
			this.cmbBOS.Location = new System.Drawing.Point(401, 25);
			this.cmbBOS.Name = "cmbBOS";
			this.cmbBOS.Size = new System.Drawing.Size(121, 21);
			this.cmbBOS.TabIndex = 8;
			// Form1
			this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);
			this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
			this.ClientSize = new System.Drawing.Size(530, 61);
			this.Name = "Form1";
			this.Text = "Form1";
			this.Load += new System.EventHandler(this.OnLoad);



		private System.Windows.Forms.Label lblAll;
		private System.Windows.Forms.ComboBox cmbAll;
		private System.Windows.Forms.Label lblNewYork;
		private System.Windows.Forms.ComboBox cmbNY;
		private System.Windows.Forms.Label lblNewJersey;
		private System.Windows.Forms.ComboBox cmbNJ;
		private System.Windows.Forms.Label lblBoston;
		private System.Windows.Forms.ComboBox cmbBOS;


Open in new window

Which produces the following output -Capture.JPGBut this then raises the question of why make the user chose a drop down item if it only has one item to choose?  Just food for thought.


Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
AndyAinscowFreelance programmer / ConsultantCommented:
>>>can you please share me the sample syntax, please

cmboBox.Enabled = false;
chokkaStudentAuthor Commented:
Thank you it_saige
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today
Visual Basic.NET

From novice to tech pro — start learning today.