foreach(DataRow ㅡ speed improvment

[patrick]

There are 124769 DataRow.


The code for statement blow is too slow.

var selectedRows = 124769 DataRows;
string str;
foreach (DataRow selectedRow in selectedrows)
{
str += ";" ;
str += selected[LOT_ID].Tostring();
}

 

[Skydiver]

It's not the foreach that is slow. It is your use of string concatenation that is slow because each += allocates a brand new string and needs to copy the old characters into the new string. Use a StringBuilder instead.

 

[patrick]

It's not the foreach that is slow. It is your use of string concatenation that is slow because each += allocates a brand new string and needs to copy the old characters into the new string. Use a StringBuilder instead.

thank you so much.

you are my teacher