50 lines
1.2 KiB
Markdown
50 lines
1.2 KiB
Markdown
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---
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title: "MVC1006: Methods containing TagHelpers must be async and return Task"
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description: "Learn about analysis rule MVC1006: Methods containing TagHelpers must be async and return Task"
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author: pranavkm
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monikerRange: '>= aspnetcore-3.1'
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ms.author: riande
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ms.date: 10/22/2021
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uid: diagnostics/mvc1006
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---
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# MVC1006: Methods containing TagHelpers must be async and return Task
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| | Value |
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| **Rule ID** |MVC1006|
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| **Fix is breaking or non-breaking** |Breaking|
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## Cause
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A tag helper was defined inside a Razor function that executes synchronously
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### Rule description
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Tag Helper execution is asynchronous. When used inside a method or a lambda within a Razor Page, the containing function must also be declared to be async.
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Consider the following cshtml file:
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```razor
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void Helper(string controller)
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{
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<a asp-controller="@controller">Home</a>
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}
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```
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`asp-controller` is a tag helper and will trigger this rule.
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## How to fix violations
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Declare the function to be async and Task returning:
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```razor
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async Task Helper(string controller)
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{
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<a asp-controller="@controller">Home</a>
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}
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```
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## When to suppress warnings
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Do not suppress a warning from this rule.
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