how to copy only the columns in a DataTable to another DataTable

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Datatable Clone is slow for large tables  I m currently using this   Dim target As DataTable        New DataView source   1 2   Nothing  DataViewRowState CurrentRows       ToTable     Note that this only copies the structure of source table  not the data

User · Answer

DataTable Clone   should do the trick    DataTable newTable   originalTable Clone

User · Answer

If you want the structure of a particular data table dataTable1  with column headers  without data  into another data table dataTable2   you can follow the below code           DataTable dataTable2   dataTable1 Clone            dataTable2 Clear      Now you can fill dataTable2 according to your condition

User · Answer

The DataTable Clone   method works great when you want to create a completely new DataTable  but there might be cases where you would want to add the schema columns from one DataTable to another existing DataTable   For example  if you ve derived a new subclass from DataTable  and want to import schema information into it  you couldn t use Clone     E g    public class CoolNewTable   DataTable      public void FillFromReader DbDataReader reader              We want to get the schema information  i e  columns  from the            DbDataReader and            import it into  this  DataTable  NOT a new one         DataTable schema   reader GetSchemaTable              GetSchemaTable   returns a DataTable with the columns we want          ImportSchema this  schema       lt --- how do we do this           The answer is just to create new DataColumns in the existing DataTable using the schema table s columns as templates    I e  the code for ImportSchema would be something like this   void ImportSchema DataTable dest  DataTable source        foreach var c in source Columns          dest Columns Add c       or  if you re using Linq   void ImportSchema DataTable dest  DataTable source        var cols   source Columns Cast lt DataColumn gt    ToArray        dest Columns AddRange cols       This was just one example of a situation where you might want to copy schema columns from one DataTable into another one without using Clone   to create a completely new DataTable  I m sure I ve come across several others as well

User · Answer

If only the columns are required then DataTable Clone   can be used  With Clone function only the schema will be copied  But DataTable Copy   copies both the structure and data  E g   DataTable dt   new DataTable    dt Columns Add  Column Name    dt Rows Add  Column Data    DataTable dt1   dt Clone    DataTable dt2   dt Copy      dt1 will have only the one column but dt2 will have one column with one row

User · Answer

If you want to copy the DataTable to another DataTable of different Schema Structure then you can do this    Firstly Clone the first DataType so that you can only get the structure  Then alter the newly created structure as per your need and then copy the data to newly created DataTable      So    Dim dt1 As New DataTable dt1   dtExcelData Clone   dt1 Columns 17  DataType   System Type GetType  System Decimal   dt1 Columns 26  DataType   System Type GetType  System Decimal   dt1 Columns 30  DataType   System Type GetType  System Decimal   dt1 Columns 35  DataType   System Type GetType  System Decimal   dt1 Columns 38  DataType   System Type GetType  System Decimal   dt1   dtprevious Copy     Hence you get the same DataTable but revised structure

[c#] how to copy only the columns in a DataTable to another DataTable?

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