daohualiuxiang
/
AspNetCore.Docs
mirror of https://github.com/dotnet/AspNetCore.Docs.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

Drop Blazor Hosting Models section (#12717) 

* Drop Blazor Hosting Models section

* Remove Disconnect and reconnect handling

* Update date
pull/12730/head
Luke Latham 2019-06-05 18:48:08 -05:00 committed by Rick Anderson
parent a8b0c2f17d
commit 44e25e9f7c
1 changed files with 1 additions and 67 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

68
aspnetcore/blazor/hosting-models.md
View File

@ -5,7 +5,7 @@ description: Understand client-side and server-side Blazor hosting models.
monikerRange: '>= aspnetcore-3.0'
ms.author: riande
ms.custom: mvc
ms.date: 05/28/2019
ms.date: 06/05/2019
uid: blazor/hosting-models
---
# Blazor hosting models
@ -148,72 +148,6 @@ To configure the SignalR client in the *Pages/\_Host.cshtml* file:
</script>
```
### Improved SignalR connection lifetime handling
Automatic reconnects can be enabled by calling the `withAutomaticReconnect` method on `HubConnectionBuilder`:
```csharp
const connection = new signalR.HubConnectionBuilder()
.withUrl("/chatHub")
.withAutomaticReconnect()
.build();
```
Without specifying parameters, `withAutomaticReconnect` configures the client to try to reconnect, waiting 0, 2, 10, and 30 seconds between each attempt.
To configure a non-default number of reconnect attempts before failure or to change the reconnect timing, `withAutomaticReconnect` accepts an array of numbers representing the delay in milliseconds to wait before starting each reconnect attempt:
```csharp
const connection = new signalR.HubConnectionBuilder()
.withUrl("/chatHub")
.withAutomaticReconnect([0, 0, 2000, 5000]) // defaults to [0, 2000, 10000, 30000]
.build();
```
### Improved disconnect and reconnect handling
Before starting any reconnect attempts, the `HubConnection` transitions to the `Reconnecting` state and fires its `onreconnecting` callback. This provides an opportunity to warn users that the connection was lost, disable UI elements, and mitigate confusing user scenarios that might occur due to the disconnected state:
```javascript
connection.onreconnecting((error) => {
console.assert(connection.state === signalR.HubConnectionState.Reconnecting);
document.getElementById("messageInput").disabled = true;
const li = document.createElement("li");
li.textContent = `Connection lost due to error "${error}". Reconnecting.`;
document.getElementById("messagesList").appendChild(li);
});
```
If the client successfully reconnects within its first four attempts, the `HubConnection` transitions back to the `Connected` state and fires `onreconnected` callback. This provides an opportunity to inform users that the connection is re-established:
```javascript
connection.onreconnected((connectionId) => {
console.assert(connection.state === signalR.HubConnectionState.Connected);
document.getElementById("messageInput").disabled = false;
const li = document.createElement("li");
li.textContent = `Connection reestablished. Connected with connectionId "${connectionId}".`;
document.getElementById("messagesList").appendChild(li);
});
```
If the client doesn't successfully reconnect within its first four attempts, the `HubConnection` transitions to the `Disconnected` state and fires its `onclosed` callback. This is an opportunity to inform users that the connection is permanently lost and to recommend refreshing the page.
```javascript
connection.onclose((error) => {
console.assert(connection.state === signalR.HubConnectionState.Disconnected);
document.getElementById("messageInput").disabled = true;
const li = document.createElement("li");
li.textContent = `Connection closed due to error "${error}". Try refreshing this page to restart the connection.`;
document.getElementById("messagesList").appendChild(li);
})
```
## Additional resources
* <xref:blazor/get-started>