Hi

I want to read the content in datareader.So I use below coding to do that
if (dataReader4.IsDBNull(0)){

}
but I run above coding it gave me an error meassage.The error Meassage is
"Invalid attempt to read when no data is present".

then I use below coding
dataReader4["Email"]==null
but It also gave me above error meassage.There is no record for that field,that only for one record,for othere records there are email address.

Thanks
Tank50

You missed Read() method.

if (dataReader4.Read())
   var=dataReader4.IsDBNull(0);
}

Hi,
Read example here. It will help you. You have to call dataReader4.Read() before reading it. If still problem persist please post code what you have done so far.

Hi

I want to read the content in datareader.So I use below coding to do that
if (dataReader4.IsDBNull(0)){

}
but I run above coding it gave me an error meassage.The error Meassage is
"Invalid attempt to read when no data is present".

then I use below coding
dataReader4["Email"]==null
but It also gave me above error meassage.There is no record for that field,that only for one record,for othere records there are email address.

Thanks
Tank50

//****************************************************
Hi,
try this code to read datareader...

// Instance a new object
Object a = new Object();

// Check if datareader is null
if (datareader == null)
return;

// Get data from datareader
while (datareader.Read())
{
// Code example...
a = datareader.GetValue(0);
}

Hope it works for you...
:idea: See ya!!!

It looks like you start using the reader without reading some data first.

void ReadData(SqlConnection conn, string sql)
SqlDataReader datareader;
SqlCommand cmd = new SqlCommand();
cmd.Connection = conn;
cmd.CommandText = sql;
datareader = cmd.ExecuteReader();
while (datareader.Read()) {
 // perform your code here
}
}

Cheers,
Dennis

Hi

Thanks guys.I was in greate trouble coz of this error meassage.Now it ok ,I miss datareader.Read() part.

:)
Tank50

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