c# - Is it possible to switch rows and columns in a datagridview?

Question

I have 10 records of data in a DataTable which has 3 fields "Foo", "Bar", and "Baz".

If I connect wire this into a DataGridView I see 10 rows and 3 columns, and the column headers display the names of the fields.

I'm wondering how easy it is to reverse the rows and columns so that with the same data I end up with 3 rows and 10 columns, with field names being displayed in the row headers.

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I can do some things manualy, like overriding an OnPaint method and drawing the field names directly into the row header cells, but I'm looking for something more automated.

Again, there's a suggestion of swapping values manualy, but unless I make all values Strings, this isn't going to work. 3 columns in a data table - Foo, Bar, and Baz of types int, float and string just won't transpose.

Even if I managed all of these manual changes, my data grids have CheckBox columns, ComboBox columns - no such row counterpart exists - there is no CheckBox row or ComboBox row. Where I currently just need to tell the compiler to "Add a ComboBoxColumn" I'd have to re-write so that every cell was generated individually.

Ideally I'd like a TransposableDataGridView which exposed all functionality of the DataGridView, with an additional bool property "Transposed". That way I could leave all of my code exactly as it is - I wouldn't have to change anything except for the type of the grid.

If nothing like this exists, I might just have to go and write it. (Should only take me a year or so! :)

Answer 1

You can create new DataTable, add appropriate number of collumns and then copy values from one table to the other, just swap rows and colums.

I don't think you can set row header in the same way you can set column header (or at least I don't know how), so you can put the field names in separate colum.

DataTable oldTable = new DataTable();

...

DataTable newTable = new DataTable();

newTable.Columns.Add("Field Name");
for (int i = 0; i < oldTable.Rows.Count; i++)
    newTable.Columns.Add();

for (int i = 0; i < oldTable.Columns.Count; i++)
{
    DataRow newRow = newTable.NewRow();

    newRow[0] = oldTable.Columns[i].Caption;
    for (int j = 0; j < oldTable.Rows.Count; j++)
        newRow[j+1] = oldTable.Rows[j][i];
    newTable.Rows.Add(newRow);
}

dataGridView.DataSource = newTable;