How to bind a Dictionary<Int32, CustomClass> to a dropdown

Question

Hi,

I've seen lots of posts about binding a dictionary to a drop down when the value is a string.

What if the value is a class with a particular property of that class being the one thats displayed in the drop down?

Dictionaty

// Value class MyClass { public String Yer="123"; public String Ner="321"; }

How do I display property Yer in my dropdown that's bound to that dictionary?

Answer 1

You need to use the DataTextField and DataValueField properties to the combo. Try this:

    private void Page_Load(object sender, EventArgs e)
    {
        List<MyDummyObject> data = new List<MyDummyObject>() 
            { 
                 new MyDummyObject() {ID = 1, RandomBoolValue = true, SomeRandomDescription = "First item" } 
                ,new MyDummyObject() {ID=2, RandomBoolValue = false, SomeRandomDescription = "Second item" }
            };

        comboBox1.DataTextField = "SomeRandomDescription";
        comboBox1.DataValueField = "ID";
        comboBox1.DataSource = data;
        comboBox1.DataBind();
    }


    private class MyDummyObject
    {
        public int ID { get; set; }
        public string SomeRandomDescription { get; set; }
        public bool RandomBoolValue { get; set; }

        public override string ToString()
        {
            return "zzzzzz";
        }
    }

The overridden ToString on MyDummyObject is just to prove that it isn't being called (which is the default action if you don't specify DataTextField or DataValueField).