Share keychain data with different apps

1. Create two projects, testwritekeychain and testreadkeychain. (add the Security. Framework library and use it to read the keychain). Then add the apple official keychainitemwrapper. h and keychainitemwrapper. M files to access the keychain.

2. Change the bundle identifier of the. plist file of the two projects to com. companyName. App. testwritekeychain and COM. companyName. App. testreadkeychain;

3. Change the entitlements of the two projects. Add the preceding two bundle identifier in the keychain access groups of the entitlements of the two projects. For example:

5. In the testwritekeychain project

-(Bool) Application :( uiapplication *) Application didfinishlaunchingwitexceptions :( nsdictionary
*) Add the following code to the launchoptions function:

Keychainitemwrapper * keychain = [keychainitemwrapperalloc]
Initwithidentifier: @ "_ test_write_keychain _" accessgroup: Nil]; // note that the accessgroup is nil,

// Read for the first time. The keychaindata should be nil because it is not set before.

Id keychaindata = [keychain objectforkey ID) ksecattraccount];

Nslog (@ "first keychaindata: % @,
% @, % D ", keychaindata, [keychaindataclass], [(nsstring
*) Keychaindatalength]);

// Write the corresponding data to the keychain. Here we write a string @ "testwritekeychain"

[Keychain setobject: @ "testwritekeychain" forkey :( ID) ksecattraccount];

// The second read, because it is not set before, keychaindata should be @ "testwritekeychain"

Keychaindata = [keychain objectforkey :( ID) ksecattraccount];

Nslog (@ "second keychaindata
: % @, % @, % D ", keychaindata, [keychaindata class], [(nsstring *) keychaindata length]);

After testwritekeychain is run, the-(bool) Application :( uiapplication *) Application in testreadkeychain
Didfinishlaunchingwitexceptions :( nsdictionary *) Add the following code to the launchoptions function:

Keychainitemwrapper * keychain = [[keychainitemwrapper alloc] initwithidentifier: @ "_ test_write_keychain _" accessgroup: Nil];

Id keychaindata = [keychain objectforkey ID) ksecattraccount];

Nslog (@ "first keychaindata: % @, % @, % d", keychaindata,
[Keychaindata class], [(nsstring *) keychaindata length]);

You can also read @ "testwritekeychain ".