using system.Linq.dynamic

public class data
 {
  public int column1{ get; set; }
  public int column2{ get; set; }
  public string column3{ get; set; }
 }
List<data> ListOfdata=new List<data>();
for(i=1:i<10;i++)
 {
  data newdata=new data();
  newdata.column1=i;
  newdata.column2=i+1;
  ListOfdata.Add(newdata)
 }

 condition1="column1!=Null AND column1=column2";

 var filter=ListOfdata.where(condition).Tolist();