Question

I am adding an object to a list and then afterwards setting the object variable to null. To add the another object to the list do i need to create a new object. The code I am using is below:

UpdateData = new MismatchData();
   UpdateData.CINID = currentInLoopCIN_ID;
   UpdateData.ColumnMapID = <some integer>;
   UpdateData.WMSValue = <some integer>;
lsMismatchData.Add(UpdateData);
UpdateData = null;

Do I need to have the first line?

UpdateData = new MismatchData(); //Do I need to have this line of code?

Answer 1

Since you’re setting UpdateDate to null, you’d get an error when you’d try to set UpdateData.CINID, the second time around (you’d be accessing a null object).

Your null assignment is the redundant line of code here. Since you’re always assigning a new UpdateData to your variable, you don’t need to reset it in between.

With or without the null assignment, you’ll still need to create a new instance every time, though, otherwise you’d just be updating the old instance.

If you want to cut down on lines of code, you could do something like this:

lsMismatchData.Add(new UpdateData {
    CINID = currentInLoopCIN_ID,
    ColumnMapID = <some new integer>,
    WMSValue = <some new integer>
});

Or, since it looks like you’re in a loop, you might be able to do something like this, to make your code even terser:

var lsMismatchData = yourLoopSource.Select(x => new UpdateData {
    CINID = x.CIN_ID, // apply your own logic to getting the proper values here.
    ColumnMapID = x.XYZ,
    WMSValue = x.ABC
}).ToList();