...s_writable: bool,
/// This account's data contains a loaded program (and is now read-only)
pub executable: bool,
}
```
### `init_if_needed`:
与 `init` 不同，`init_if_needed` 不那么严格，使用起来很灵活。`init_if_needed` 类似于 `init`，但它不像 `init` 那...
...;
// If user is not connected to the Rinkeby network, let them know and throw an error
const { chainId } = await web3Provider.getNetwork();
if (chainId !== 4) {
window.alert("Change the network to Rinkeby");
throw new Error("Change network to Rinkeby");
}
con...