How can i check column is null?

Question

User-1909885141 posted

in asp.net, i select some data by using below query.

And There is code that get user_nm from datatable.

DataTable test = "select user_id from users";

test.rows[0]["user_nm"]

so below code made error.

test.rows[0]["user_nm"]

How can i check column is null?

Answer 1

User-1629691846 posted

You can use DBNull.value.Equals()

if (! DBNull.Value.Equals(test.row[0]["user_nm"])) 
   {
      //not null
   }
   else
   {
      //null
   }

OR 

you can get the value in object first as :

object value = test.row[0]["user_nm"];
    if (value == DBNull.Value)
{
}
else
{
}

Answer 2

User607059406 posted

yes he is right you can check and use the non null value

Answer 3

User3866881 posted

How can i check column is null?

Hi,

Just try this——

if(test.Rows[0]["ColumnName"] ==null || test.Rows[0]["ColumnName"] == DbNull.Value)
{
} 

Answer 4

User-1758105784 posted

                    if (!string.IsNullOrEmpty(test.Rows[0]["REQUIRED_QTY"].ToString()))
                     {
                         //Do Something.........
                      }

Hope This Will Help