[Feat] Allow dynamic DataSource type to AddColumn

[timiil]

hi , it is a nice project .

in the runtime AddColumn() mode, we must access the ITable< DataSource > instance, but in many context, we even dit not have the 'DataSource' type definition in code. it is just an ITable,

@code {

private ITable table;

...

protected override void OnAfterRender(bool firstRender)
    {
        base.OnAfterRender(firstRender);
        if (firstRender)
        {
            var col = new Column()
            {
                Title = "some desc",
                //Field = f => f.Summary,
                FieldName = "Summary",           //pls allow string field selector rather than lambda field here :)
                Sortable = true,
                Filterable = true,
                Width = "10%"
            };

            this.table.AddColumn(col);            //for now, ITable dit not have AddColumn api :(

            
        }

}

[nicky-ernste]

I know this is an older question but perhaps it can still help someone.

I also ran into this. But i used a simple ExpressionTree to build this dynamically too. I made a little method that you can try using.

private Expression<Func<T, object>> GetFieldExpression<T>(string fieldName)
{
    var parameter = Expression.Parameter(typeof(T), "t");
    var propertyExpression = Expression.PropertyOrField(parameter, fieldName);
    return Expression.Lambda<Func<T, object>>(Expression.Convert(propertyExpression, typeof(object)), parameter);
}

In your example you can use it as follows:

var col = new Column<ColumnType>()
{
    Title ="some desc",
    Field = GetFieldExpression<ColumnType>("Summary")
};
this.table.AddColumn(col);

This works pretty well for me to load columns dynamically using reflection. Just make sure to change ColumnType to the type you are displaying in your table (ie your TableItem).