C # basic string processing

• Locate string
  String STR = "ABCD ";
  Int M1 = Str. indexof ("B ");// M1 = 1
  Int m2 = Str. indexof ("cd ");// M2 = 2
  Int m3 = Str. indexof ("");// M3 = 0
  Int M4 = Str. indexof ("W ");// M4 =-1

 

• Format a string
  String str1 = string. Format ("(c) Currency: {0: c} \ n",-123.45678f );
  // Format it to the currency type; str1 = (c) Currency: ￥-123.46
  String str1 = string. Format ("(d) Short Date: {0: d} \ n", datetime. Now );
  // Format it to the time type; str1 = (d) Short Date:
  

  Character	Description	Example	Output
  C	Currency	String. Format ("{0: C3}", 2)	$2.000
  D	Decimal	String. Format ("{0: D3}", 2)	002
  E	Scientific notation	1.20e + 001	1.20e + 001
  G	General	String. Format ("{0: g}", 2)	2
  N	Number separated by semicolons	String. Format ("{0: n}", 250000)	250,000.00
  X	Hexadecimal	String. Format ("{0: x000}", 12)	C
  		String. Format ("{0: 000. 000}", 12.2)	012.200

 

• Truncate string
  String STR = "Hello world! ";
  String str1 = Str. substring (0, 5 );// Str1 = "hello ";

 

• Comparison string
  // Compareto (): If the value of the parameter is equal to that of the instance, 0 is returned. If the value of this parameter is greater than the value of the parameter, 1 is returned. Otherwise,-1 is returned.
  String str1 = "ABC ";
  String M1 = str1.compareto ("ABC ");// M1 = 0
  String m2 = str1.compareto ("AB ");// M2 = 1
  String m3 = str1.compareto ("ABCD ");// M3 =-1
  // Equals (): If the parameter value is the same as that of the instance, the parameter value is true. Otherwise, the parameter value is false.
  String str1 = "ABC", str2 = "ABC", str3 = "ABC ";
  Bool b1 = str1.equals (str2 );// B1 = false
  Bool b2 = str1.equals (str3 );// B2 = true