OC and C language comparison

Description: Comparative memory is relatively easier to remember firmly, understand the C language relative to OC is not too difficult, OC is the C language extension, backward-compatible C language.

Comparison of source file suffix names

1.C Language source files

. h: Header files

. C: Source files

. O: Target file

. Out: Executable file

2.OC Language source files

. h: Header files

. m: Source file

. mm:oc++ Source Files

Data type Comparison

Common types in the C language:

Common types in OC

Note: New types in OC

Keyword comparison

Attention:

1.OC compatible with C language, C language keywords can be used in OC

2. If you use the keywords in oc, some keywords need to start with "@"

Add: The basic usage of "@"

1. Represents a string object that converts C into OC NSString

Most of the keywords in 2.OC start with @

OC and C language comparison