从多个不均匀列表创建数据表的最佳方法是什么 <T> ？

Question

I have 4 lists of 'List' with different kind of data(text) and number of items in each list is also not same. What would be the best way to create data table from those lists?

Ex.

class A {
  public int id {get; set;}
  public string Name {get; set;}
  public string detailInfo {get; set;}
}

class B {
  public string info {get; set;}
}

class C {
  public string Code {get; set;}
}

class D {
  public int contact {get; set;}
  public int contact2 {get; set;}
  public Addr {get; set;}
}

class E {
  main() {
    IList<A> listA= new List<A>();
    IList<B> listB= new List<B>();
    IList<C> listC= new List<C>();
    IList<D> listC= new List<D>();
  }
}

So from above 4 lists what will be the best way to create data table? Note:Number of items in each list may vary..

Answer 1

I'd define the column names with reflection and just iterate over the records in your list to populate the rows. Something like this:

public DataTable GetDataTable<T>(List<T> list) where T : class
{
   DataTable table = new DataTable();
   var fields = typeof(T).GetFields();

   //Create Columns
   foreach(var field in fields)
   {
      DataColumn c = new DataColumn(field.Name, field.GetType());
      c.AllowDbNull = true;
      table.Columns.Add(c);
   }

   //Create rows
   foreach(T record in list)
   {
      DataRow row = table.NewRow();

      foreach(var field in fields)
      {
         //If it's null the cell will contain DbNull.Value
         if(field.GetValue(record) != null)
            row[field.Name] = field.GetValue(record);
      }

      table.Rows.Add(row);
   }

   return table;
}

This will give you a datatable with as columnNames the propertynames of your classes and as rows the values of each record in the list. If one of your properties is null, the datatable will contain DbNull.Value .

Answer 2

@Alexander I managed to populate required table using below code:

public static DataTable ToDataTable<T>(List<T> items)
{
        DataTable dataTable = new DataTable(typeof(T).Name);

        //Get all the properties
        PropertyInfo[] Props = typeof(T).GetProperties(BindingFlags.Public | BindingFlags.Instance)`enter code here`;
        foreach (PropertyInfo prop in Props)
        {
            //Setting column names as Property names
            dataTable.Columns.Add(prop.Name);
        }
        foreach (T item in items)
        {
           var values = new object[Props.Length];
           for (int i = 0; i < Props.Length; i++)
           {
                //inserting property values to datatable rows
                values[i] = Props[i].GetValue(item, null);
           }
           dataTable.Rows.Add(values);
      }
      return dataTable;
}