Csharp/C Sharp/Class Interface/ToString
Содержание
- 1 class declaration maintains the time in 24-hour format and ToString Method
- 2 demonstrates overriding the ToString() method to provide a custom string output
- 3 Demonstrate ToString()
- 4 Format data in ToString method.
- 5 Illustrates how to override the ToString() method
- 6 .NET Frameworks Overview:Custom Object Formatting
- 7 Overriding the ToString() Method
class declaration maintains the time in 24-hour format and ToString Method
<source lang="csharp">
using System; public class Time1 {
private int hour; // 0 - 23
private int minute; // 0 - 59
private int second; // 0 - 59
public void SetTime( int h, int m, int s )
{
hour = ( ( h >= 0 && h < 24 ) ? h : 0 );
minute = ( ( m >= 0 && m < 60 ) ? m : 0 );
second = ( ( s >= 0 && s < 60 ) ? s : 0 );
}
public string ToUniversalString()
{
return string.Format( "{0:D2}:{1:D2}:{2:D2}",
hour, minute, second );
}
public override string ToString()
{
return string.Format( "{0}:{1:D2}:{2:D2} {3}",
( ( hour == 0 || hour == 12 ) ? 12 : hour % 12 ),
minute, second, ( hour < 12 ? "AM" : "PM" ) );
}
} public class Time1Test {
public static void Main( string[] args )
{
Time1 time = new Time1();
Console.WriteLine( time.ToUniversalString() );
Console.WriteLine( time.ToString() );
time.SetTime( 13, 27, 6 );
Console.WriteLine( time.ToUniversalString() );
Console.WriteLine( time.ToString() );
time.SetTime( 99, 99, 99 );
Console.WriteLine( time.ToUniversalString() );
Console.WriteLine( time.ToString() );
}
}
</source>
demonstrates overriding the ToString() method to provide a custom string output
<source lang="csharp"> /* C# Programming Tips & Techniques by Charles Wright, Kris Jamsa Publisher: Osborne/McGraw-Hill (December 28, 2001) ISBN: 0072193794
- /
// tm1.cs - demonstrates overriding the ToString() method to provide a custom // string output. // // Compile this program using the following command line: // D:>csc tm1.cs // namespace nsStructure {
using System;
using System.Globalization;
public struct tm
{
public int tm_sec; // Seconds after the minute
public int tm_min; // Minutes after the hour
public int tm_hour; // Hours since midnight
public int tm_mday; // The day of the month
public int tm_mon; // The month (January = 0)
public int tm_year; // The year (00 = 1900)
public int tm_wday; // The day of the week (Sunday = 0)
public int tm_yday; // The day of the year (Jan. 1 = 1)
public int tm_isdst; // Flag to indicate if DST is in effect
public override string ToString()
{
const string wDays = "SunMonTueWedThuFriSat";
const string months = "JanFebMarAprMayJunJulAugSepOctNovDec";
return (String.Format ("{0} {1} {2,2:00} " +
"{3,2:00}:{4,2:00}:{5,2:00} {6}\n",
wDays.Substring (3 * tm_wday, 3),
months.Substring (3 * tm_mon, 3),
tm_mday, tm_hour, tm_min,
tm_sec, tm_year + 1900));
}
}
public class tm1
{
static public void Main()
{
DateTime timeVal = DateTime.Now;
tm tmNow = LocalTime (timeVal);
Console.WriteLine (tmNow);
}
static public tm LocalTime(DateTime tmVal)
{
tm time;
time.tm_sec = tmVal.Second;
time.tm_min = tmVal.Minute;
time.tm_hour = tmVal.Hour;
time.tm_mday = tmVal.Day;
time.tm_mon = tmVal.Month - 1;
time.tm_year = tmVal.Year - 1900;
time.tm_wday = (int) tmVal.DayOfWeek;
time.tm_yday = tmVal.DayOfYear;
TimeZone tz = TimeZone.CurrentTimeZone;
time.tm_isdst = tz.IsDaylightSavingTime (tmVal) == true ? 1 : 0;
return (time);
}
}
}
</source>
Demonstrate ToString()
<source lang="csharp"> /* C#: The Complete Reference by Herbert Schildt Publisher: Osborne/McGraw-Hill (March 8, 2002) ISBN: 0072134852
- /
// Demonstrate ToString()
using System;
class MyClass {
static int count = 0;
int id;
public MyClass() {
id = count;
count++;
}
public override string ToString() {
return "MyClass object #" + id;
}
}
public class Test {
public static void Main() {
MyClass ob1 = new MyClass();
MyClass ob2 = new MyClass();
MyClass ob3 = new MyClass();
Console.WriteLine(ob1);
Console.WriteLine(ob2);
Console.WriteLine(ob3);
}
}
</source>
Format data in ToString method.
<source lang="csharp">
using System;
public class Time1
{
private int hour;
private int minute;
private int second;
public void SetTime( int h, int m, int s )
{
hour = ( ( h >= 0 && h < 24 ) ? h : 0 );
minute = ( ( m >= 0 && m < 60 ) ? m : 0 );
second = ( ( s >= 0 && s < 60 ) ? s : 0 );
}
public string ToUniversalString()
{
return string.Format( "{0:D2}:{1:D2}:{2:D2}", hour, minute, second );
}
public override string ToString()
{
return string.Format( "{0:D2}:{1:D2}:{2:D2} {3}",
( ( hour == 0 || hour == 12 ) ? 12 : hour % 12 ),
minute, second, ( hour < 12 ? "AM" : "PM" ) );
}
} public class MemberAccessTest {
public static void Main( string[] args )
{
Time1 time = new Time1();
time.hour = 7; // error: hour has private access in Time1
time.minute = 15; // error: minute has private access in Time1
time.second = 30; // error: second has private access in Time1
}
}
</source>
Illustrates how to override the ToString() method
<source lang="csharp"> /* Mastering Visual C# .NET by Jason Price, Mike Gunderloy Publisher: Sybex; ISBN: 0782129110
- /
/*
Example7_7.cs illustrates how to override the ToString() method
- /
using System;
// declare the Car class class Car {
// declare the fields
public string make;
public string model;
// define a constructor
public Car(string make, string model)
{
this.make = make;
this.model = model;
}
// override the ToString() method
public override string ToString()
{
return make + " " + model;
}
}
public class Example7_7 {
public static void Main()
{
// create Car objects
Console.WriteLine("Creating Car objects");
Car myCar = new Car("Toyota", "MR2");
Car myOtherCar = new Car("Porsche", "Boxter");
// call the ToString() method for the Car objects
Console.WriteLine("myCar.ToString() = " +
myCar.ToString());
Console.WriteLine("myOtherCar.ToString() = " +
myOtherCar.ToString());
}
}
</source>
.NET Frameworks Overview:Custom Object Formatting
<source lang="csharp"> using System; class Employee: IFormattable {
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));
}
int id;
string firstName;
string lastName;
} public class CustomObjectFormatting {
public static void Main()
{
Employee fred = new Employee(123, "AAA", "BBB");
Console.WriteLine("No format: {0}", fred);
Console.WriteLine("Full format: {0:F}", fred);
}
}
</source>
Overriding the ToString() Method
<source lang="csharp"> using System;
public class Name {
public string firstName;
public string lastName;
public Name(string firstName, string lastName) {
this.firstName = firstName;
this.lastName = lastName;
}
public void Display() {
Console.WriteLine("firstName = " + firstName);
Console.WriteLine("lastName = " + lastName);
}
// override the ToString() method
public override string ToString() {
return firstName + " " + lastName;
}
} class Test{
public static void Main() {
Name myName = new Name("T", "M");
Name myOtherName = new Name("P", "B");
// call the ToString() method for the Name objects
Console.WriteLine("myName.ToString() = " + myName.ToString());
Console.WriteLine("myOtherName.ToString() = " + myOtherName.ToString());
}
}
</source>
