Check if datareader is empty

Question

I'm constant receive the error:

Additional information: Data is Null. This method or property cannot be called on Null values.

When I try to receive information. How can I check if the datareader is empty.

for example this is my code:

 while (rd.Read())
            {
                if (rd.HasRows)
                {
                    foundInformation[0] = rd.GetString(0);
                    foundInformation[1] = rd.GetString(1);
                }
                else
                {
                    foundInformation[0] = "nvt";
                    foundInformation[1] = "nvt";
                }               
            }

How can I check if rd.GetString(0) is empty?

Thankyou.

You check for rows but GetString goes for a column... – Thomas Ayoub Jun 04 '15 at 14:25 — Thomas Ayoub, Jun 04 '15 at 14:25
there is the IsDBNull method in the data reader – Ahmed ilyas Jun 04 '15 at 14:25 — Ahmed ilyas, Jun 04 '15 at 14:25

score 9 · Accepted Answer · answered Jun 04 '15 at 14:26

9

You need to call IsDBNull before you call GetString.

if (!rd.IsDBNull(0))
{
  //...
}

https://msdn.microsoft.com/en-us/library/system.data.sqlclient.sqldatareader.isdbnull%28v=vs.110%29.aspx

answered Jun 04 '15 at 14:26

William Xifaras

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Check if datareader is empty

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