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Using linq to sql can I easily copy a large record in c#

Given this (this being in a loop where "header" is a different linq object):

hdrTable hdr = (from hh
in dc.hdrTable_sqls
where hh.ord_no == header.po_no
orderby hh.ID descending
select hh).FirstOrDefault();

hdrTable_sql newhdr = new hdrTable_sql();

newhdr.rcv_exch_rt_fg = null;
newhdr.inv_exch_rt_fg = null;
newhdr.updt_in_progress = null;
newhdr.hst_dt = DateTime.Now.Date;
newhdr.hst_tm = captureTime;

//TODO: set the rest of the fields

Is there a way to set the values of all the columns in hdrTable to be equal to the values of the corresponding columns in hdr without actually entering hdrTable.col1 = hdr.col1, etc.?

The table has 150 columns, and I am trying to find a shortcut.

AndyAinscow

You could loop through the fields collection
x.Fields(i) = y.Fields(i)
BUT they must have the same number of fields and in the same order

Fernando Soto

Hi g_johnson;

THIS ONLY WORKS WITH Linq To Entity Framework.

The following code snippet is the simplest way to do what you need to do.

// you create your data context
var dc = new ....;

// Turn off proxy creation so that it does not interfere
// when adding the new entity to the data context
dc.Configuration.ProxyCreationEnabled = false;

hdrTable hdr = ( from hh in dc.hdrTable_sqls
                 where hh.ord_no == header.po_no
                 orderby hh.ID descending
                 select hh).FirstOrDefault();

// Create the copy of the record.
hdrTable newhdr = hdr.ShallowCopy();
// Replace TABLEID with the Primary key name oand 
// setting it to zero
newhdr.TABLEID = 0;
newhdr.rcv_exch_rt_fg = null;
newhdr.inv_exch_rt_fg = null;
newhdr.updt_in_progress = null;
newhdr.hst_dt = DateTime.Now.Date;
newhdr.hst_tm = captureTime;

// We create a new patial class for the hdrTable
// to add a ShallowCopy method. We add it here
// and not in the original class so that if you 
// regenerate the model it will NOT over write this method
using System;

namespace "Replace With The Namespace of the table with the same name"
{
    public partial class hdrTable
    {
        public hdrTable ShallowCopy()
        {
            return (hdrTable)this.MemberwiseClone();
        }
    }
}

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Fernando Soto

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g_johnson

ASKER

Hi. I was just in the last couple of days able to get back to this project and test this. Thank you for the help!