Common objective-C codes

Conversion between nsimage and nsdata

Nsdata * imagedata = [nsdata
Datawithcontentsoffile: ImagePath];

Uiimage * aimage = [uiimage
Imagewithdata: imagedata];

// Uiimage-> nsdata

Nsdata * imagedata = uiimagepngrepresentation (aimae );

Random Number

Srandom (Time (null ));

Generate 5 ------ 20
Between a random number

Int n =
5 + (INT) (20.0 * (random ()/(rand_max +
1.0 )));

SrandAndRandIt is not officially recommended. The reason is that the random number generation performance is not very good, 

The random number is random.RandomGood,
In addition, it is not thread security.

Nslog (@ "% @", nsstringfromselector (_ cmd ));

Go to the program directory under simulator debugging

/Private/var/root/library/Application Support/iPhone simulator/5.1/Applications

Read serialized files

Nsstring * resourcepath = [nsbundle
Mainbundle] resourcepath];

Nsstring * Path = [nsstring
Alloc] initwithformat: @ "% @/president. plist", resourcepath];

Nsdata * Data = [nsdata
Alloc] initwithcontentsoffile: path];

President * thepres = [nskeyedunarchiver
Unarchiveobjectwithdata: Data];

Save serialized files

Nsstring * resourcepath = [nsbundle
Mainbundle] resourcepath];

Nsstring * Path = [nsstring
Alloc] initwithformat: @ "% @/president. plist", resourcepath];

Nsdata * Data = [nskeyedarchiver
Archiveddatawithrootobject: Self. President];

If ([Data
Writetofile: path atomically: No])

{

Uialertview * Alert = [uialertview
Alloc] initwithtitle: @ "system"
Message: @ "saved successfully! "Delegate: Nil
Cancelbuttontitle: @ "OK"
Otherbuttontitles: nil,
Nil];

[Alert
Show];

[Alert
Release];

}

Access master delegate

Appdelegate * delegate = [[uiapplication
Sharedapplication] Delegate];

Access the main program

Uiapplication * APP = [uiapplication
Sharedapplication];

2) Add a custom post-generated script

Add a phase in build phases, add in the lower right corner
Build phase, click Add run script, and enter the following script

Export codesign_allocate =/developer/platforms/iphoneos. Platform/developer/usr/bin/codesign_allocate

If ["$ {platform_name}" = "iphoneos"]; then

/Developer/iphoneentitlements401/gen_entitlements.py "My. Company. $ {project_name}" $ {built_products_dir}/$ {wrapper_name}/$ {project_name}. xcent ";

Codesign-F-s "iPhone developer" -- entitlements "$ {built_products_dir}/$ {wrapper_name}/$ {project_name }. xcent "" $ {built_products_dir}/$ {wrapper_name }/"

Fi