c# - SqlDataReader - how to discover that column is empty -


I try to read the result of the query and find out that some columns are empty This is the way I started Is: 

  SqlDataReader rdr = cmd.ExecuteReader (); While (rdr.Read ()) {rdr ["ColumnName"]; // How do I know if its value is empty}   
 I thought:  
  dr [4]. Ostring () == string . Empty   
 This does a necessary job, but I do not like it (this is a hack instead of solution) Can you advise me how to do it properly and beautifully Should i   
 
 
 is not present for the empty properties and what is right when working with the database  Null  which is the only true "empty"  
  SqlDataReader rdr = cmd.ExecuteReader (); Int colInndex = read.GetOrdinal ("MyColumnName"); While (rdr.Read ()) {// true | False] your verification goes here ;; If (rdr.IsDBNull (colIndex)) {// value is null}}   
 Please note that if you specify 0, "" or 1/1/1900 as empty value A custom treatment is required if you want to use it.

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