C # stream byte char string stream, byte, character, string

1. Two different methods calculate the length of a string

String strtmp = "wk986 Wang Kedong ";

Int I = system. Text. encoding. Default. getbytes (strtmp). length;// Calculate the length of Chinese Characters
Int J = strtmp. length;// The length of a Chinese character is not counted

Console. writeline ("string {0}, count the length of Chinese characters: {1}, not count the length of Chinese characters: {2}", strtmp, I, j );

// Convert to an array to calculate the length of the array

Byte [] bytstr = system. Text. encoding. Default. getbytes (strtmp );
Int Len = bytstr. length;
Console. writeline ("String Length:" + Len. tostring ());
Console. Read ();

 

2. system. Text. stringbuilder ("")

It is different from the string "+". In C #, the string is of the "Reference" type. Each addition creates a new string. When the string is very large, high Performance consumption, so use stringbuilder.

System. Text. stringbuilder sb = new system. Text. stringbuilder ("");
SB. append ("China ");
SB. append ("people ");
SB. append ("Republic ");
Console. writeline (SB );

// Determine the number of Chinese Characters

Private int chkgbklen (string Str)
{
System. Text. asciiencoding n = new system. Text. asciiencoding ();
Byte [] B = n. getbytes (STR );
Int L = 0;
For (INT I = 0; I <= B. Length-1; I ++)
{
If (B [I] = 63) // determines whether it is a Chinese character or full-legged symbol.
{
L ++;
}
}
Return L;
}

C # stream, byte, character, string

First, you must understand what they are composed: Stream:Binary Byte:Unsigned integer Character:Unicode characters String:Multiple Unicode characters In. net, how can they be converted? Generally, the following rules are observed: Stream-> byte array-> character array-> string The conversion syntax is described as follows: Stream-> byte array Memorystream MS = new memorystream (); Byte [] buffer = new byte [Ms. Length]; Ms. Read (buffer, 0, (INT) ms. Length ); Byte array-> stream Byte [] buffer = new byte [10]; Memorystream MS = new memorystream (buffer ); Byte array-> character array 1. Byte [] buffer = new byte [10]; Char [] CH = new asciiencoding (). getchars (buffer ); // Or: Char [] CH = encoding. utf8.getchars (buffer) 2. Byte [] buffer = new byte [10]; Char [] CH = new char [10]; For (INT I = 0; I <buffer. length; I ++) { Ch [I] = convert. tochar (buffer [I]); } Character array-> byte array 1. Char [] CH = new char [10]; Byte [] buffer = new asciiencoding (). getbytes (CH ); // Or: byte [] buffer = encoding. utf8.getbytes (CH) 2. Char [] CH = new char [10]; Byte [] buffer = new byte [10]; For (INT I = 0; I <Ch. length; I ++) { Buffer [I] = convert. tobyte (CH [I]); } Character array-> string Char [] CH = new char [10]; String STR = new string (CH ); String> character array String STR = "ABCDE "; Char [] CH = Str. tochararray (); Byte array-> string Byte [] buffer = new byte [10]; String STR = system. Text. encoding. utf8.getstring (buffer ); // Or: String STR = new asciiencoding (). getstring (buffer ); String> byte array String STR = "ABCDE "; Byte [] buffer = system. Text. encoding. utf8.getbytes (STR ); // Or: byte [] buffer = new asciiencoding (). getbytes (STR ); Note: The convert class and the class in the system. Text namespace are used. encoding is a static class, asciiencoding is an entity class, and the methods are the same!