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  "framework" : "HealthKit",
  "identifier" : "/documentation/HealthKit/HKHealthStore/bloodType()",
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  "title" : "bloodType()"
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# bloodType()

Reads the user’s blood type from the HealthKit store.

```
func bloodType() throws -> HKBloodTypeObject
```

## Return Value

A blood type object that contains information about the user’s blood type.

## Discussion

If the user has not specified a blood type or if the user has denied your app permission to read the blood type, this method returns an [`HKBloodType.notSet`](/documentation/HealthKit/HKBloodType/notSet) value.

> Handling Errors in Swift:
> In Swift, this method returns a nonoptional result and is marked with the `throws` keyword to indicate that it throws an error in cases of failure.
> 
> You call this method in a `try` expression and handle any errors in the `catch` clauses of a `do` statement, as described in [Error Handling](https://docs.swift.org/swift-book/LanguageGuide/ErrorHandling.html) in [The Swift Programming Language](https://docs.swift.org/swift-book/) and `About Imported Cocoa Error Parameters`.

## Topics

### Possible Values

[`HKBloodTypeObject`](/documentation/HealthKit/HKBloodTypeObject)

This class acts as a wrapper for the [`HKBloodType`](/documentation/HealthKit/HKBloodType) enumeration.

[`HKBloodType`](/documentation/HealthKit/HKBloodType)

Constants indicating the user’s blood type.


---

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