rust - 如何在基板模块中将块号转换为整数类型？

Question

我正在测试substrate off-chain worker，我想要做的是接收当前的块号，然后做一些计算，就像下面的代码一样if (get_block / 10 == 0)，我得到了一些错误。如何将块号转换为 Integer 类型？

我的代码

use frame_support::{decl_storage, decl_module, dispatch::DispatchResult, debug};

use frame_system::{ensure_signed, offchain};

use sp_runtime::{
  offchain::http,
  transaction_validity::{
    TransactionValidity, TransactionLongevity, ValidTransaction, InvalidTransaction
  }
};

pub trait Trait: frame_system::Trait {}

decl_storage! {
    trait Store for Module<T: Trait> as Runtime_example {
        SubjectCount: u32;        
    }
}
decl_module! {
    pub struct Module<T: Trait> for enum Call where origin: T::Origin {
        fn offchain_worker(block: T::BlockNumber){
            let get_block = block;
            if (get_block / 10 == 0) {  
               debug::info!("print !!!!!!!!!!!!!!!!");               
            }            
        }
    }
}

错误日志

error[E0308]: mismatched types
  --> /home/substrate-node-template/runtime/src/runtime_example.rs:32:29
   |
32 |             if (get_block / 10 == 0) {  
   |                             ^ expected associated type, found integer
   |
   = note: expected associated type `<T as frame_system::Trait>::BlockNumber`
                         found type `{integer}`
   = help: consider constraining the associated type `<T as frame_system::Trait>::BlockNumber` to `{integer}` or calling a method that returns `<T as frame_system::Trait>::BlockNumber`

error[E0308]: mismatched types
  --> /home/substrate-node-template/runtime/src/runtime_example.rs:32:34
   |
32 |             if (get_block / 10 == 0) {  
   |                                  ^ expected associated type, found integer
   |
   = note: expected associated type `<T as frame_system::Trait>::BlockNumber`
                         found type `{integer}`
   = help: consider constraining the associated type `<T as frame_system::Trait>::BlockNumber` to `{integer}` or calling a method that returns `<T as frame_system::Trait>::BlockNumber`

标签： rustblockchainsubstrate

Answer 1

@kmdreko 是对的。您不想将块号转换为整数，而是将整数转换为块号，然后进行数学运算。

所以替换：

get_block / 10 == 0

和：

(get_block / 10.into()).is_zero()