英文:
React SignalR HubConnection doesn't send data to server
问题
我正在尝试创建一个连接到 SignalR Hub 并在按钮点击时发送信息的应用程序，但出于某种原因它没有发送任何信息。
const bannerId = 1;
const App = () => {
useEffect(() => {
let newConnection = new HubConnectionBuilder()
.withUrl('https://localhost:7116/bannerHub')
.withAutomaticReconnect()
.build();
setConnection(newConnection);
}, []);
useEffect(() => {
if (connection) {
connection.start()
.then(result => {
console.log('Connected!');
})
.catch(e => console.log('Connection failed: ', e));
}
}, [connection]);
const disableBanner = async (evt) => {
await connection.send('DisableBanner', bannerId);
}
const enableBanner = async (evt) => {
await connection.send('EnableBanner', bannerId);
}
return (
<>
<button onClick={async () => { await disableBanner(); }} className='btn btn-primary'>Disable banner</button>
<button onClick={async () => { await enableBanner(); }} className='btn btn-primary'>Enable banner</button>
</>
);
}
我使用的包是 @microsoft/signalr，而 connection 对象是一个 HubConnection。
有人知道我做错了什么吗？
谢谢，希望对其他遇到相同问题的人有所帮助！
英文:
I'm trying to do an application that connects to a SignalR hub and sends information when buttons are clicked but for some reason it's not sending anything.
<!-- begin snippet: js hide: false console: true babel: false -->
<!-- language: lang-js -->
const bannerId = 1;
const App = () => {
useEffect(() => {
let newConnection = new HubConnectionBuilder()
.withUrl('https://localhost:7116/bannerHub')
.withAutomaticReconnect()
.build();
setConnection(newConnection);
}, []);
useEffect(() => {
if (connection) {
connection.start()
.then(result => {
console.log('Connected!');
})
.catch(e => console.log('Connection failed: ', e));
}
}, [connection]);
const disableBanner = async (evt) => {
await connection.send('DisableBanner', bannerId);
}
const enableBanner = async (evt) => {
await connection.send('EnableBanner', bannerId);
}
return(
<>
<button onClick={async () => { await disableBanner(); }} className='btn btn-primary'>Disable banner</button>
<button onClick={async () => { await enableBanner(); }} className='btn btn-primary'>Enable banner</button>
</>
);
}
<!-- end snippet -->
The package that I'm using is @microsoft/signalr and the connection object it's a HubConnection.
Does anyone knows what am I doing wrong?
Thank you and I hope this helps to others with the same problem!
答案1
得分: 0
I've solve it.
My problem was on the server side. SignalR methods where waiting for a string bannerId and I was sending them an int (or Number in JS). I thought that data binding was going to fix this but for some reason that doesn't work here.
The two possible solutions are:
- 将 SignalR 方法更改为接收
int bannerId而不是string bannerId - 将 React 组件更改为发送
bannerId: string而不是bannerId: number。
That was all. Thank you all for the comments.
英文:
I've solve it.
My problem was on the server side. SignalR methods where waiting for a string bannerId and I was sending them an int (or Number in JS). I thought that data binding was going to fix this but for some reason that doesn't works here.
The two possible solutions are:
- Change the SignalR methods to receive
int bannerIdinstead ofstring bannerId - Change react component to send a
bannerId: stringinstead ofbannerId: number.
That was all. Thank you all for the comments.
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