String and stringbuilder

C # supports two types of strings: Rule string and verbatim string.

I previously saw that when the @ + "" structure is used to process strings, I just wrote down how to use it. In fact, this is a standard verbatim string and the characters between separators are interpreted word-by-word, the only exception is quotation marks. In a verbatim string, a string does not process simple escape sequences, hexadecimal and Unicode escape sequences, and can span multiple rows. For example:

 

Static void main (string [] ARGs)
{
String S = "this major \" teacher \ "is too Spam! ";
String S1 = @ "this major" "teacher" "is too Spam! ";
Console. writeline ("s-{0}", S1 );
Console. writeline ("S1-{0}", S1 );
String S2 = @ "this major
Instructor
Too Spam! ";
Console. writeline ("S2-{0}", S2 );
Console. readkey ();

The difference between string and stringbuilder can be summarized as stringbuilder is a variable character sequence similar to the string class. We all know that string is a new reference of a new value and must be allocated with new memory. In this way, we can use stringbuilder to improve performance when we change or connect many strings multiple times. First, we will demonstrate some representative methods and attribute usage of string and stringbuilder respectively:

Using system;

Namespace tstring
{
Class Test
{
Static void main ()
{
// Connection string demonstration
String S1 = "today is ";
String S2 = "Tuesday! ";
String S = S1 + S2;
Console. writeline (s );
Console. writeline ("equivalent to: String. Concat (S1, S2) S = {0}", String. Concat (S1, S2 ));
// Verbatim access string demonstration
Console. writeline ("verbatim access string demonstration \ n Method 1 :");
Foreach (char C in S) // method 1
{
Console. Write (C + "");
}
Console. writeline ("\ n method 2 ");
Char [] STR = S. tochararray (); // copy the characters in S to the Unicode character array
Foreach (char R in Str)
{
Console. Write (R + "");
}
Console. writeline ("\ n method 3 ");
For (INT I = 0; I <S. length; I ++) // The index starts with 0, and the second is not the location of the Unicode character.
{
Console. Write (s [I] + "");
}
S = S1 + S2;
// Method for searching test characters
Console. writeline ("Method for searching test characters ");
Console. writeline ("the index of the first character matching \" today \ "is {0}", S. indexof ("today "));
String target = "Ido"; // note that I only found this experiment, comparing it with the target character by character.
Char [] anyof = target. tochararray ();
Int start = 0;
Int;
At = S. indexofany (anyof, start );
If (at>-1)
Console. writeline ("the index of the first character matching \" ID \ "in S is {0}", );
Else
Console. writeline ("(not found )");
Char [] n = {'I', s '};
// Example:
Char [] AR = {'I', s '};
Console. writeline (the index of the first character matching \ "is \" in "s is {0}", S. indexofany (AR ));
Console. writeline ("the substring corresponding to index 0-5 is {0}", S. substring (0, 5 ));
// Modify the string
Console. writeline ("modifying string test ");
// Insert
Console. writeline ("insert test ");
Console. writeline (S. insert (17, "What a nice weather! "));
// Padleft
Console. writeline ("padleft test ");
S = S. padleft (S. Length + 8 ,'♀');
Console. writeline (s );
// Padright
Console. writeline ("padright test ");
S = S. padright (S. Length + 8 ,'♂');
Console. writeline (s );
Console. readkey ();
}
}
}

 

 

: To reduce power consumption, only the string class can be demonstrated. You can study the strigbuilder class by yourself, which is similar to the string class. Several typical methods include append, appendformat, and tostring.