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copied!<p>i think this can be done by using a <code>TypeDescriptionProvider</code>.</p> <p><strike>the BAD news is: i have never done this before and won't be able to provide much help</strike></p> <p>the GOOD news is: i've found an example here: <a href="https://stackoverflow.com/questions/1468840/datagridview-not-showing-properites-of-objects-which-implement-icustomtypedescrip">DataGridView not showing properites of objects which implement ICustomTypeDescriptor</a></p> <p>//edit</p> <p>i used the code (see link above) to build an example how to avoid the dictionary per object ... </p> <pre><code>public class myRow { //your data storage class ... public string txt { get; set; } public int id { get; set; } } public class MyView:ICustomTypeDescriptor {//your extendable view class ... private static PropertyDescriptorCollection props = null; static MyView() { TypeDescriptionProvider defaultProvider = TypeDescriptor.GetProvider(typeof(MyView)); props = new PropertyDescriptorCollection(defaultProvider.GetTypeDescriptor(typeof(MyView)).GetProperties().Cast<PropertyDescriptor>().ToArray(), true); } public static void addProperty(string name, DataTable dt, Func<DataRow, object> getter, Action<DataRow, object> setter, Func<DataTable, MyView, DataRow> rowSelector, Type PropType) { List<PropertyDescriptor> tmp; if (props != null) tmp = props.Cast<PropertyDescriptor>().ToList(); else tmp = new List<PropertyDescriptor>(); PropertyDescriptor pd = TypeDescriptor.CreateProperty(typeof(MyView), name, PropType, null); pd = new MyViewPropertyDescriptor(pd, dt, getter, setter, rowSelector, PropType); tmp.Add(pd); props = new PropertyDescriptorCollection(tmp.ToArray(), true); } //the data storage obj this view is referencing public myRow obj; public string TXT { // view-member known at compile time get { return obj.txt; } set { obj.txt = value; } } internal class MyViewPropertyDescriptor : PropertyDescriptor { // an example property descriptor that can link to data in a DataTable ... DataTable dt; Func<DataRow, object> getter; Action<DataRow, object> setter; Func<DataTable, MyView, DataRow> rowSelector; Type type; public MyViewPropertyDescriptor(PropertyDescriptor descr, DataTable dt, Func<DataRow, object> getter, Action<DataRow, object> setter, Func<DataTable, MyView, DataRow> rowSelector, Type PropType) : base(descr) { this.dt = dt; // storage for additional data referenced by this property this.getter = getter; //a getter that will take a DataRow, and extract the property value this.setter = setter; //a setter that will take a DataRow and a value this.rowSelector = rowSelector;//a row selector ... takes a dataset and the view object and has to return the assiciated datarow this.type = PropType; // the type of this property } public override object GetValue(object component) { // using row selector and getter to return the current value ... you should add errorhandling here return getter(rowSelector(dt, (MyView)component)); } public override void SetValue(object component, object value) { // the setter ... needs errorhandling too setter(rowSelector(dt, (MyView)component), value); } public override void ResetValue(object component) { } public override bool CanResetValue(object component) { return false; } public override bool ShouldSerializeValue(object component) { return false; } public override Type PropertyType { get { return type; } } public override bool IsReadOnly { get { return false; } } public override Type ComponentType { get { return typeof(MyView); } } } ICustomTypeDescriptor defaultDescriptor = TypeDescriptor.GetProvider(typeof(MyView)).GetTypeDescriptor(typeof(MyView)); AttributeCollection ICustomTypeDescriptor.GetAttributes() { return defaultDescriptor.GetAttributes(); } string ICustomTypeDescriptor.GetClassName() { return defaultDescriptor.GetClassName(); } string ICustomTypeDescriptor.GetComponentName() { return defaultDescriptor.GetComponentName(); } TypeConverter ICustomTypeDescriptor.GetConverter() { return defaultDescriptor.GetConverter(); } EventDescriptor ICustomTypeDescriptor.GetDefaultEvent() { return defaultDescriptor.GetDefaultEvent(); } PropertyDescriptor ICustomTypeDescriptor.GetDefaultProperty() { return defaultDescriptor.GetDefaultProperty(); } object ICustomTypeDescriptor.GetEditor(Type editorBaseType) { return defaultDescriptor.GetEditor(editorBaseType); } EventDescriptorCollection ICustomTypeDescriptor.GetEvents(Attribute[] attributes) { return defaultDescriptor.GetEvents(attributes); } EventDescriptorCollection ICustomTypeDescriptor.GetEvents() { return defaultDescriptor.GetEvents(); } PropertyDescriptorCollection ICustomTypeDescriptor.GetProperties(Attribute[] attributes) { return props; // should really be filtered, but meh! } PropertyDescriptorCollection ICustomTypeDescriptor.GetProperties() { return props; } object ICustomTypeDescriptor.GetPropertyOwner(PropertyDescriptor pd) { return this; } } </code></pre> <p>and a little example that makes use of this ...</p> <pre><code>private void button1_Click(object sender, EventArgs e) { if (dataGridView1.DataSource == null) { List<myRow> data = new List<myRow>(); data.Add(new myRow { id = 1, txt = "test 1" }); data.Add(new myRow { id = 2, txt = "test 2" }); data.Add(new myRow { id = 3, txt = "test 3" }); DataTable dt = new DataTable(); dt.Columns.Add("id", typeof(int)); dt.Columns.Add("additionalData1", typeof(int)); dt.Columns.Add("additionalData2", typeof(int)); Random rnd = new Random(); foreach (var item in data) { dt.Rows.Add(new object[] { item.id, rnd.Next(), rnd.Next() }); } MyView.addProperty("additionalData1", dt, row => row["additionalData1"], (row, val) => row["additionalData1"] = val, (tab, v) => tab.Rows.OfType<DataRow>().First(x => x["id"].Equals(v.obj.id)), typeof(int)); MyView.addProperty("additionalData2", dt, row => row["additionalData2"], (row, val) => row["additionalData2"] = val, (tab, v) => tab.Rows.OfType<DataRow>().First(x => x["id"].Equals(v.obj.id)), typeof(int)); dataGridView1.DataSource = new BindingList<MyView>(data.Select(x => new MyView { obj = x }).ToList()); } } </code></pre> <p>of course you will want to provide a better rowSelector or replace the DataTable with a Hashtable or whatever datastructure you want ... just an example</p>

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