Two elements: string and escape characters

Strings String.

1. Immutability: Once the assignment is changed, each time the string changes, the pointer points to the new string.

2. Can be used: a new string can be produced between strings using the concatenation operator (+).

3. Common Properties: Length indicates string lengths, and the int type is obtained.

4. Common methods:

Trim (): de-lettering;

ToUpper (): converted to uppercase;

ToLower (): converted to lowercase form;

Split (): Split

Replace (): replacement

Remove (): Remove

LastIndexOf (): Last occurrence position

IsNullOrEmpty: Is null or a null character

IndexOf: The first occurrence of the position

Format: Replace

equals: Is it equal

5. Escape character:

Escape character meaning
\ ' Single-quote character
\ "single-quote character
\ \ backslash character "\"
A/s null character (NULL)
\a Ringing Bell
\b Backspace
\f Paper Change page
\ nthe line break
\ r Enter
\ t jumps horizontally to the next tab position
\v Vertical tabs (vertical tab)

In C #, "c:\\temp" means that the path is C:\Temp
and @ "C:\Temp" means C:\Temp
So, the action of @ should be to ignore the escape character.

Two elements: string and escape characters