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POConvert SqlDataReader to a List of unknown types because of dynamic query
 

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  1. POConvert SqlDataReader to a List of unknown types because of dynamic query
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    <p>Friends, I have a dynamic sql query that I would like to execute and return a list. From most of my internet searches on goole, I found that the type of the list has to be known to convert the sqldatareader to a list. How can I do that when I do not know what query will be executed.</p> <pre><code>Execute(String query) { SqlConnection con=new SqlConnection(connection);//connection from elsewhere SqlCommand cmd = new SqlCommand(query); cmd.connection=con; con.Open(); SqlDataReader result=cmd.ExecuteReader(); //How to convert result to a list when i do not know the table structure } </code></pre> <p>Now I want to convert the result to a list. However I do not know the details of the table which the query works on.The query can vary, it can query any table. So under these conditions how can I convert the result to a list. Is it possible?</p> <p>This leaves me with one simple question, if I do not know the table details, then what will be the entries of the list or it will be a list of what?</p> <p>To answer that question, I ask myself another question, is it possible to have a list where each list entry will correspond to one row of the SqlDataReader result?</p> <p>So I can use a List &lt; DataRow > x =result.Select().ToList(), but I do not want to use this either.</p> <p>I want each entry of the list to map to each row of the result and at the same time be composed of the atomic datatypes which make a row.</p> <p>Eg <strong>Select studentname,studentid from student;</strong> This will return me a SqlDataReader result and I want to construct a list whose type contains a string and an int and then populate the list with the rows of the result.</p> <p>When the query changes to <strong>select marks,subject,grade from marks where studentid=1432</strong>, then I want to construct a list whose type contains int,string,char and then fill the list with the rows of the result.</p> <p>Is there a way to do it? </p> <p>PS The user knows how to pick the values if I return a list as detailed above, since he created the query and he knows how many columns to expect.</p>
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    1. USdavid
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    1. COcan't you use a SqlTableAdapter ? you'll get a collection of DataRow, whichever is the schema of the result
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      1. USSteve B
 

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