.web3provider----->前端與合約互動(需要提供provider)--->不同rpc,chainid ![](https://i.imgur.com/nq0Rwcl.png) --- [useState用法](https://www.youtube.com/watch?v=bUyVYTbUNy4) ### useState用法---->array destructing用法 [array destructing](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Destructuring_assignment) ![](https://i.imgur.com/cr5j2Si.png) --- ![](https://i.imgur.com/LUkfHFB.png) * [Usestate參考影片](https://www.youtube.com/watch?v=bUyVYTbUNy4&ab_channel=PJCHENder)