Set the property to look for in JsonDerivedType

[vsfeedback]

This issue has been moved from a ticket on Developer Community.

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.NET 7 provide polymophic deserialisation. Works fine but the way it is implemented has some drawbacks.

1. it only looks for the $Type property in a json object
2. $Type must be the first property in a json object

change requests

• rename typeDiscriminator to typeDiscriminatorValue
• add typeDiscriminatorName = the name of the property to look for and match its value with the typeDiscriminatorValue
• do not require the typediscriminator property to be the first property in the json

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Original Comments

Feedback Bot on 6/20/2023, 08:31 PM:

(private comment, text removed)

[ghost]

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Issue Details

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This issue has been moved from a ticket on Developer Community.

---

.NET 7 provide polymophic deserialisation. Works fine but the way it is implemented has some drawbacks.

1. it only looks for the $Type property in a json object
2. $Type must be the first property in a json object

change requests

• rename typeDiscriminator to typeDiscriminatorValue
• add typeDiscriminatorName = the name of the property to look for and match its value with the typeDiscriminatorValue
• do not require the typediscriminator property to be the first property in the json

---

Original Comments

Feedback Bot on 6/20/2023, 08:31 PM:

(private comment, text removed)

Author:	vsfeedback
Assignees:	-
Labels:	area-System.Text.Json, untriaged
Milestone:	-

[eiriktsarpalis]

it only looks for the $Type property in a json object

The actual name of type discriminator property can be configured using the JsonPolymorphic attribute.

$Type must be the first property in a json object

This is tracked by #72604. We expect a fix to make its way in .NET 9.

rename typeDiscriminator to typeDiscriminatorValue

Renaming APIs that have already shipped is a breaking change that we couldn't consider, unfortunately.

Hope this answers your questions.