c# - Is there a neat way to compare nullable and dbnullable objects? -


i have code this:

foreach (datarow row in datatable.rows) {         if ((string)row["forename"] != record.forename)         {               //         } }

works great if row["forename"] null in database, dbnull here , can't cast dbnull string, or perform comparison between dbnull , string. values nullable<int>, , can't compare dbnull int?

is there helper method let me nice comparisons or have write extension method myself?

you can use datarow.field extension method supports nullable types:

foreach (datarow row in datatable.rows) {     int? id = row.field<int?>("id");     if(id.hasvalue)     {         console.write("id: " + id.value);     } }

since string reference type null default. can use datarow.isnull instead check whether dbnull.value or not:

foreach (datarow row in datatable.rows) {     if(row.isnull("forename"))     {         // ...     }      else     {         string forename = row.field<string>("forename");         console.write("forename: " + forename);     } }

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