c# - structured variables pass to method becomes zero? -

unity c# global struct variable treated local surprised need seek advise. in start:

struct st{ public float f; public bool b_toprocess;}st st; st = new st(){b_toprocess = true}; 

in update:

if(st.b_toprocess) process(st); 

somewhere in same .cs:

process(st st){     debug.log("f:" + st.f); // 0     st.f += 0.1f; if( st.f > 5){b_toprocess = false;}     debug.log("f:" + st.f); // 0.1f } 

but process run never-ending !!!! logs showed f 0 on start of each , subsequent iteration , after += 0.1f never greater 5. right should accumulative on each iteration. question is: how come st.f @ 0 on each iteration. local variable treated way passed in struct variable.

please some1 advise. thanks.

my psychic debugging powers telling me expect struct behave reference type.

in c#, structs value types.

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when call process(), whole struct copied, not reference. change in struct not reflected in struct in calling method.

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if make class instead, will behave reference type.

you can use ref keyword

process(ref st st) {    ... } 

and call this

if(st.b_toprocess)      process(ref st);