# ReferenceExpressionBuilderInterpolatedStringHandler

- Kind: `struct`
- Package: [Aspire.Hosting](/reference/api/csharp/aspire.hosting.md)
- Version: `13.3.0`
- Namespace: `Aspire.Hosting.ApplicationModel`
- Target framework: `net8.0`
- Source: [GitHub](https://github.com/microsoft/aspire/blob/bd20f904cde09ecb9c9ae5116a6f13614bf2d7c2/src/Aspire.Hosting/ApplicationModel/ReferenceExpression.cs)

Represents a handler for interpolated strings that contain expressions. Those expressions will either be literal strings or instances of types that implement both [IValueProvider](/reference/api/csharp/aspire.hosting/ivalueprovider.md) and [IManifestExpressionProvider](/reference/api/csharp/aspire.hosting/imanifestexpressionprovider.md).

## Definition

```csharp
namespace Aspire.Hosting.ApplicationModel;

public sealed struct ReferenceExpressionBuilderInterpolatedStringHandler
{
    // ...
}
```

## Constructors

- [ReferenceExpressionBuilderInterpolatedStringHandler(int, int, ReferenceExpressionBuilder)](/reference/api/csharp/aspire.hosting/referenceexpressionbuilderinterpolatedstringhandler/constructors.md#constructor-int-int-referenceexpressionbuilder) -- Represents a handler for interpolated strings that contain expressions. Those expressions will either be literal strings or instances of types that implement both [IValueProvider](/reference/api/csharp/aspire.hosting/ivalueprovider.md) and [IManifestExpressionProvider](/reference/api/csharp/aspire.hosting/imanifestexpressionprovider.md).

## Methods

- [AppendFormatted(string?)](/reference/api/csharp/aspire.hosting/referenceexpressionbuilderinterpolatedstringhandler/methods.md#appendformatted-string) -- Appends a formatted value to the expression.
- [AppendFormatted(string?, string)](/reference/api/csharp/aspire.hosting/referenceexpressionbuilderinterpolatedstringhandler/methods.md#appendformatted-string-string) -- Appends a formatted value to the expression.
- [AppendFormatted(ReferenceExpression, string)](/reference/api/csharp/aspire.hosting/referenceexpressionbuilderinterpolatedstringhandler/methods.md#appendformatted-referenceexpression-string) `obsolete` -- Appends the formatted value provided by the specified reference expression to the output.
- [AppendFormatted(T)](/reference/api/csharp/aspire.hosting/referenceexpressionbuilderinterpolatedstringhandler/methods.md#appendformatted-t) -- Appends a formatted value to the expression. The value must implement [IValueProvider](/reference/api/csharp/aspire.hosting/ivalueprovider.md) and [IManifestExpressionProvider](/reference/api/csharp/aspire.hosting/imanifestexpressionprovider.md).
- [AppendFormatted(T, string?)](/reference/api/csharp/aspire.hosting/referenceexpressionbuilderinterpolatedstringhandler/methods.md#appendformatted-t-string) -- Appends a formatted value to the expression. The value must implement [IValueProvider](/reference/api/csharp/aspire.hosting/ivalueprovider.md) and [IManifestExpressionProvider](/reference/api/csharp/aspire.hosting/imanifestexpressionprovider.md).
- [AppendFormatted(IResourceBuilder<T>)](/reference/api/csharp/aspire.hosting/referenceexpressionbuilderinterpolatedstringhandler/methods.md#appendformatted-iresourcebuilder-t) -- Appends a formatted value to the expression. The value must implement [IValueProvider](/reference/api/csharp/aspire.hosting/ivalueprovider.md) and [IManifestExpressionProvider](/reference/api/csharp/aspire.hosting/imanifestexpressionprovider.md).
- [AppendFormatted(IResourceBuilder<T>, string?)](/reference/api/csharp/aspire.hosting/referenceexpressionbuilderinterpolatedstringhandler/methods.md#appendformatted-iresourcebuilder-t-string) -- Appends a formatted value to the expression. The value must implement [IValueProvider](/reference/api/csharp/aspire.hosting/ivalueprovider.md) and [IManifestExpressionProvider](/reference/api/csharp/aspire.hosting/imanifestexpressionprovider.md).
- [AppendLiteral(string)](/reference/api/csharp/aspire.hosting/referenceexpressionbuilderinterpolatedstringhandler/methods.md#appendliteral-string) -- Appends a literal value to the expression.