c# modifying structs in a List

Question

Short question: How can I modify individual items in a List? (or more precisely, members of a struct stored in a List?)

Full e

Answer 1

Looking at the for-loop approach, the reason (and solution) for this is given in the documentation for the compilation error:

An attempt was made to modify a value type that is produced as the result of an intermediate expression but is not stored in a variable. This error can occur when you attempt to directly modify a struct in a generic collection.

To modify the struct, first assign it to a local variable, modify the variable, then assign the variable back to the item in the collection.

So, in your for-loop, change the following lines:

catSlots[s].subItems.Clear();
catSlots[s].subItems = sortedSubTemp;   // ERROR: see below

...into:

slotInfo tempSlot = gAllCats[0].items[s];
tempSlot.subItems  = sortedSubTemp;
gAllCats[0].items[s] = tempSlot;

I removed the call to the Clear method, since I don't think it adds anything.