How to access specific row in datareader ?

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Hi , I got Memory out Of Exception while download bulk reports . So i alter the code by using DATAREADER instead of DATASET . How to achieve below code in DataReader because am helpless to use any datatables & dataset in my coding.

What I have tried:

C#

if (dataSet.Tables[0].Rows[i + 1]["Sr No"].ToString() == dataSet.Tables[0].Rows[i]["Sr No"].ToString())

Posted 1-Aug-16 20:21pm

Vicky Siddharth

Updated 2-Aug-16 2:24am

v4

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Tomas Takac 2-Aug-16 2:34am

I don't understand, what is stopping you from using datareader["Sr No"]?

Vicky Siddharth 2-Aug-16 2:41am

Hi Tomas. while(datareader.read()) { i)loop goes for the first time it takes 1 record from record set
ii) here i want to access the 2 record value .
}
how can we achieve ?

Karthik_Mahalingam 2-Aug-16 11:04am

Always use Reply button to post comments/query to the concerned user, else the user wont get notified.

Vicky Siddharth 3-Aug-16 8:36am

ok karthik

Karthik_Mahalingam 3-Aug-16 8:38am

:)

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OriginalGriff · Accepted Answer · 2016-08-01T21:34:00

A DataReader only works by reading forward through the data set: you can't specify a random access value to "skip" to a specific row.
The only way to access a row in a DataReader is to use a loop to read each row up to the point where you reach the row you want. But...you can't go "backward" to earlier rows once you have gone past them.
If you are having problems reading all the rows at once, then consider either "paging" the number of rows you read into a DataAdapter, or issue individual read requests for just the rows you are interested in.

Tomas Takac · Accepted Answer · 2016-08-02T02:24:00

DataReader has no random access. You need to "remember" the value from previous row.

C#

string previous = null;
string current = null;
bool isFirst = true;

while (datareader.Read())
{
    current = datareader["Sr No"].ToString();
    
    if (isFirst)
    {
        // skip the first row because we don't have anything to compare it to
        isFirst = false;
    }
    else if(current == previous)
    {
        // do your thing here
    }
    
    previous = current;
}

How to access specific row in datareader ?

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