Create customized format for Complex
using System;
using System.Text;
using System.Globalization;
public struct Complex : IFormattable
{
public Complex( double real, double imaginary ) {
this.real = real;
this.imaginary = imaginary;
}
public string ToString( string format,IFormatProvider formatProvider ) {
StringBuilder sb = new StringBuilder();
if( format == "DBG" ) {
sb.Append( this.GetType().ToString() + "\n" );
sb.AppendFormat( "\treal:\t{0}\n", real );
sb.AppendFormat( "\timaginary:\t{0}\n", imaginary );
} else {
sb.Append( "( " );
sb.Append( real.ToString(format, formatProvider) );
sb.Append( " : " );
sb.Append( imaginary.ToString(format, formatProvider) );
sb.Append( " )" );
}
return sb.ToString();
}
private double real;
private double imaginary;
}
public class MainClass
{
static void Main() {
CultureInfo local = CultureInfo.CurrentCulture;
CultureInfo germany = new CultureInfo( "de-DE" );
Complex cpx = new Complex( 12.3456, 1234.56 );
string strCpx = cpx.ToString( "F", local );
Console.WriteLine( strCpx );
strCpx = cpx.ToString( "F", germany );
Console.WriteLine( strCpx );
Console.WriteLine( "\nDebugging output:\n{0:DBG}", cpx );
}
}( 12.35 : 1234.56 )
( 12,35 : 1234,56 )
Debugging output:
Complex
real: 12.3456
imaginary: 1234.56
Custom Format Specifiers
Format Character Purpose
0 Display zero placeholder
# Display digit placeholder
. Decimal point
, Group separator
% Percent notation
E+0 Exponent notation
E-0
e+0
e-0
\ Literal character
"ABC" Literal string
"ABC"
; Section separator
Custom Object Formatting
using System;
class Employee: IFormattable
{
int id;
string firstName;
string lastName;
public Employee(int id, string firstName, string lastName)
{
this.id = id;
this.firstName = firstName;
this.lastName = lastName;
}
public string ToString (string format, IFormatProvider fp)
{
if ((format != null) && (format.Equals("F")))
return(String.Format("{0}: {1}, {2}", id, lastName, firstName));
else
return(id.ToString(format, fp));
}
}
class MainClass
{
public static void Main()
{
Employee fred = new Employee(123, "First", "Last");
Console.WriteLine("No format: {0}", fred);
Console.WriteLine("Full format: {0:F}", fred);
}
}No format: 123
Full format: 123: Last, First
format as currency
using System;
class Class1
{
static void Main(string[] args)
{
string s;
int x = 2, y = 4;
double[] numArray = {12, 15, 14.5, 145.43, 200};
// format as currency
Console.WriteLine( "\n\nCurrency\n--------" );
foreach( double num in numArray )
{
Console.Write( "{0:C}\t", num );
}
}
}format as custom
using System;
class Class1
{
static void Main(string[] args)
{
string s;
int x = 2, y = 4;
double[] numArray = {12, 15, 14.5, 145.43, 200};
// format as custom
Console.WriteLine( "\n\nCustom\n------" );
foreach( double num in numArray )
{
Console.WriteLine( "{0:$#,# + $.#0;} = {0:$#,#.00}", num );
}
}
}format in lowercase hex
using System;
class Class1
{
static void Main(string[] args)
{
string s;
int x = 2, y = 4;
double[] numArray = {12, 15, 14.5, 145.43, 200};
// format in lowercase hex
Console.WriteLine( "\n\nHex (lower)\n-----------" );
foreach( double num in numArray )
{
Console.Write( "0x{0:x8}\t", (int)num );
}
}
}format in uppercase hex
using System;
class Class1
{
static void Main(string[] args)
{
string s;
int x = 2, y = 4;
double[] numArray = {12, 15, 14.5, 145.43, 200};
// format in uppercase hex
Console.WriteLine( "\n\nHex (upper)\n-----------" );
foreach( double num in numArray )
{
Console.Write( "0x{0:X8}\t", (int) num );
}
}
}Formatting flags
String Description
C Local currency format.
D Decimal format.
E Scientific (exponential) format.
F Fixed-point format;
G General format. Uses E or F formatting, depending on which is the most compact.
N Number format.
P Percent format.
X Hexadecimal format.
Formatting Using System.Console.WriteLine()
class MainClass
{
static void Main()
{
string firstName;
string lastName;
firstName = "A";
lastName = "B";
System.Console.WriteLine("Your full name is {0} {1}.",firstName, lastName);
}
}Swapping the Indexed Placeholders and Corresponding Variables
class MainClass
{
static void Main()
{
string firstName;
string lastName;
firstName = "A";
lastName = "B";
System.Console.WriteLine("Your full name is {1}, {0}",firstName, lastName);
}
}The value n various formats
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
class Program
{
static void Main(string[] args)
{
Console.WriteLine("c format: {0:c}", 99999);
Console.WriteLine("d9 format: {0:d9}", 99999);
Console.WriteLine("f3 format: {0:f3}", 99999);
Console.WriteLine("n format: {0:n}", 99999);
}
}Upper or lower casing for hex determines if letters are upper/lowercase
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
class Program
{
static void Main(string[] args)
{
Console.WriteLine("E format: {0:E}", 99999);
Console.WriteLine("e format: {0:e}", 99999);
Console.WriteLine("X format: {0:X}", 99999);
Console.WriteLine("x format: {0:x}", 99999);
}
}Using the \n Character to Insert a Newline
class MainClass
{
static void Main()
{
System.Console.Write("\"this is a test.\"");
System.Console.Write("\n\"Wait "til I get going!\"\n");
}
}
