How to bind list to dataGridView?

Question

I seem to be running around in circles and have been doing so in the last hours.

I want to populate a datagridview from an array of strings. I've read its not possible directly, and that I need to create a custom type that holds the string as a public property. So I made a class:

public class FileName
    {
        private string _value;

        public FileName(string pValue)
        {
            _value = pValue;
        }

        public string Value
        {
            get 
            {
                return _value;
            }
            set { _value = value; }
        }
    }

this is the container class, and it simply has a property with the value of the string. All I want now is that string to appear in the datagridview, when I bind its datasource to a List.

Also I have this method, BindGrid() which I want to fill the datagridview with. Here it is:

    private void BindGrid()
    {
        gvFilesOnServer.AutoGenerateColumns = false;

        //create the column programatically
        DataGridViewTextBoxColumn colFileName = new DataGridViewTextBoxColumn();
        DataGridViewCell cell = new DataGridViewTextBoxCell();
        colFileName.CellTemplate = cell; colFileName.Name = "Value";
        colFileName.HeaderText = "File Name";
        colFileName.ValueType = typeof(FileName);

        //add the column to the datagridview
        gvFilesOnServer.Columns.Add(colFileName);

        //fill the string array
        string[] filelist = GetFileListOnWebServer();

        //try making a List<FileName> from that array
        List<FileName> filenamesList = new List<FileName>(filelist.Length);
        for (int i = 0; i < filelist.Length; i++)
        {
            filenamesList.Add(new FileName(filelist[i].ToString()));
        }

        //try making a bindingsource
        BindingSource bs = new BindingSource();
        bs.DataSource = typeof(FileName);
        foreach (FileName fn in filenamesList)
        {
            bs.Add(fn);
        }
        gvFilesOnServer.DataSource = bs;
    }

Finally, the problem: the string array fills ok, the list is created ok, but I get an empty column in the datagridview. I also tried datasource= list<> directly, instead of = bindingsource, still nothing.

I would really appreciate an advice, this has been driving me crazy.

Answer 1

Use a BindingList and set the DataPropertyName-Property of the column.

Try the following:

...
private void BindGrid()
{
    gvFilesOnServer.AutoGenerateColumns = false;

    //create the column programatically
    DataGridViewCell cell = new DataGridViewTextBoxCell();
    DataGridViewTextBoxColumn colFileName = new DataGridViewTextBoxColumn()
    {
        CellTemplate = cell, 
        Name = "Value",
        HeaderText = "File Name",
        DataPropertyName = "Value" // Tell the column which property of FileName it should use
     };

    gvFilesOnServer.Columns.Add(colFileName);

    var filelist = GetFileListOnWebServer().ToList();
    var filenamesList = new BindingList<FileName>(filelist); // <-- BindingList

    //Bind BindingList directly to the DataGrid, no need of BindingSource
    gvFilesOnServer.DataSource = filenamesList 
}

Answer 2

may be little late but useful for future. if you don't require to set custom properties of cell and only concern with header text and cell value then this code will help you

public class FileName
{        
     [DisplayName("File Name")] 
     public string FileName {get;set;}
     [DisplayName("Value")] 
     public string Value {get;set;}
}

and then you can bind List as datasource as

private void BindGrid()
{
    var filelist = GetFileListOnWebServer().ToList();    
    gvFilesOnServer.DataSource = filelist.ToArray();
}

for further information you can visit this page Bind List of Class objects as Datasource to DataGridView

hope this will help you.

Answer 3

I know this is old, but this hung me up for awhile. The properties of the object in your list must be actual "properties", not just public members.

public class FileName
{        
     public string ThisFieldWorks {get;set;}
     public string ThisFieldDoesNot;
}

Answer 4

Instead of create the new Container class you can use a dataTable.

DataTable dt = new DataTable();
dt.Columns.Add("My first column Name");

dt.Rows.Add(new object[] { "Item 1" });
dt.Rows.Add(new object[] { "Item number 2" });
dt.Rows.Add(new object[] { "Item number three" });

myDataGridView.DataSource = dt;

More about this problem you can find here: http://psworld.pl/Programming/BindingListOfString

Answer 5

Using DataTable is valid as user927524 stated. You can also do it by adding rows manually, which will not require to add a specific wrapping class:

List<string> filenamesList = ...;
foreach(string filename in filenamesList)
      gvFilesOnServer.Rows.Add(new object[]{filename});

In any case, thanks user927524 for clearing this weird behavior!!