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  "title" : "setWEPKey(_:flags:index:)"
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# setWEPKey(_:flags:index:)

Sets the interface WEP key.

```
func setWEPKey(_ key: Data?, flags: CWCipherKeyFlags, index: Int) throws
```

## Parameters

`key`

An NSData object containing the WEP key.

`flags`

An NSUInteger indicating which cipher key flags to use for the specified key.

`index`

An NSUInteger indicating which default key index to use for the specified key.

## Discussion

*key* must be 5 octets for WEP-40 or 13 octets for WEP-104. If *key* is *nil*, this method clears the WEP key for the interface. *index* must correspond to default key index 1-4.

> Handling Errors in Swift:
> In Swift, this method returns `Void` 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`.

---

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