"foundation" string

first, some common classes in the foundation framework

String type:

NSString: Immutable string

Nsmutablestring: Variable string

Set Type:

1) Nsarray:oc Non-variable group

Nsmutablearray: Variable Array

2) Nsset:

Nsmutableset:

3) Nsdictiorary

Nsmutabledictiorary

Other:

NSDate

NSObject

Ii. use and attention of nsstring and nsmutablestring (i) 6 ways to create a string

(ii) use of attention(1) Import and export of strings

(2) class method

(iii) Use and attention of nsmutablestring

(iv) URL supplemental content

URL: Resource Path

Format: protocol Header:/path

Network Path Protocol header: HTTP

Local files with file as protocol header

FTP is the protocol header, stating that the resource is on the FTP server.

"foundation" string