oc-2-string

Course Highlights:

• Differences between C-language strings and OC language strings
• The difference between a class method and an object method
• Understand the differences between nsstring (mutable strings) and nsmutablestring (immutable strings)
• NSString (Immutable string)
• nsmutablestring (variable string)
• Discrimination between NSString and nsmutablestring use

Differences between C-language strings and OC language strings

  // in the C-language phase we define a string variable in the following format:  
  char//  char is the data type of the character, CString is the variable name, * is a pointer, where he plays the role is, represents CString is a          string variable // the            format of defining a string variable in the OC phase is the same /// However at this point NSString is no longer called a data type in OC, but is called a class, Ocstring is no longer called a variable name but is called an object. * This is still a pointer, which represents the declared object is the NSString type. 

PS: In C we say that the string is actually an array, and the array contains each character in the string. In OC, each string object is indeed a string.

String

#pragma mark----------Understand the difference between nsstring (immutable strings) and nsmutablestring (mutable strings)-----------

#pragma mark------------------nsstring (immutable string)----------------

#pragma mark to create a string constant

#pragma mark to create a formatted string heap area

#pragma the mark string comparison

#pragma the conversion of the Mark string

Interception and splicing of #pragma mark string

#pragma mark---------nsmutablestring (variable string)------

PS: All of the previous operations on NSString (immutable strings) We are all processing the entire string, unable to make a single string to be added to the operation of the check. Now let's use nsmutablestring (variable string) for additional

#pragma Mark added

#pragma mark Delete

#pragma mark changed

#pragma mark.

oc-2-string