Reorder dataTable columns

Question

I'm reordering my dataTable columns using :

dataTable.Columns[int x].SetOrdinal(int y)

However, I use it for each column and that doesn't to work for me.

For instance :

dataTable.Columns[0].SetOrdinal(1);
dataTable.Columns[1].SetOrdinal(0);

Makes a double inversion...

And in my code, I have to define where each column must be.

Is there any solution to this ?

Thank you.

Answer 1

This process seems easy but not really such easy. The point is whenever you change the Ordinal of a column from x to a lower ordinal a (a < x) then all the columns with ordinals between a and x will be shifted right, if x is changed to a higher ordinal b (b > x) then all the columns with ordinals between x and b wil be shifted left. We must perform some update each time a column's ordinal is changed.

You can prepare a list of your column indices in the order you want, something like this:

List<int> indices = new List<int>{1,2,0,7,4,5,3,6};

for(int i = 0; i < indices.Count; i++){
   dataTable.Columns[indices[i]].SetOrdinal(i);
   if(indices[i] > i){
      for(int j = i; j < indices.Count; j++)
         if(indices[j] >= i && indices[j] < indices[i]) indices[j]++;//Right shifted                       
   }
   else if(indices[i] < i){
      for(int j = i; j < indices.Count; j++)
         if(indices[j] >= indices[i] && indices[j] < i) indices[j]--;//Left shifted
   }
}    

Or you can also prepare a list of your ColumnName in the order you want, something like this:

List<string> columns = new List<string>{"Column2","Column1","Column5","Column3","Column6","Column4"};
//The same code as above

Answer 2

You should change columns order in a loop from array of column name that each column name placed in correct order in array. For more information go to this link : How to change DataTable columns order