Noob question: Reset Struct Variables

[declawd]

Hello,

I would like to reset all of the variables within a struct object. So for example:

struct LotsaFloats
{
float a, b, c, d, e, f, g
} Assignment1, Assignment2;

Then code goes forth utilizing Assignment1.a and Assignment1.g etc...

Now I want to reset all values for Assignment1 to 0. How do I do that?

I tried:
LotsaFloats Assignment1 = { 0 };

This did not work.

However, individually doing the following:
Assignment1.a = 0;
Assignment1.b = 0;
etc...

DOES work. But this is unwieldy. Suggestions?

[webJose]

Use memset:

memset(&Assignment1, 0, sizeof(Assignment1))

[Moooce]

Some suggestion ( open to criticism :o) )

1) Write a function that sets each variable to 0 and call it for the structure you have created.

2) Instead of using individual names for each float, create an array and use a for loop to initialise each element to 0.

3) (maybe MS specific) use ZeroMemory() function on a pointer to your structure?
http://www.cplusplus.com/forum/general/21822/

[anonymous23323124]

Or give your struct a default constructor which resets all the variables, and then use that.

[declawd]

Awesome, thanks for the answers

[Disch]

My input:

1) memset is fine as long as your struct is a POD struct. As soon as you add a complex type (like a string) memset will cause your program to explode. Since this isn't "future proof" I would recommend against it (you might want to add a string later -- and if you do you'll have to go back and change all the memsets in your program)

2) ZeroMemory is just a macro that calls memset. They're exactly the same.

3) A combination of Mooce's #1 suggestion and Xander's suggestion is what I recommend. Write a function that resets/zeros the struct, then make a default ctor that calls that function.

4) Mooce's #2 suggestion is also good if applicable. Although I would still put the resetting in a function.

[declawd]

Thanks for the clarification. Xander314 could you provide an example of how to define and call this constructer within my struct? Thanks

[declawd]

oh wait I got it.

struct LotsaFloats
{
float a, b, c, d, e, f, g
LotsaFloats()
{
a = 0; b = 0; c = 0; etc...
}
} Assignment1, Assignment2;

then I called using:

Assignment1 = LotsaFloats();

[anonymous23323124]

Yes, that's the right kind of thing :)

[pkbhavnani]

There is no need to do "Assignment1 = LotsaFloats(); "
The moment the variable Assignment1 is created, it is going to call the constructor, which is going to set all the values to zero as specified in the constructor.