C# Examples
Dave Braunschweig
Strings
// This program demonstrates string functions.
using System;
class Strings
{
public static void Main (string[] args)
{
String str = "Hello";
Console.WriteLine("string: " + str);
Console.WriteLine("string.ToLower(): " + str.ToLower());
Console.WriteLine("string.ToUpper(): " + str.ToUpper());
Console.WriteLine("string.IndexOf('e'): " + str.IndexOf('e'));
Console.WriteLine("string.Length: " + str.Length);
Console.WriteLine("string.Replace('H', 'j'): " + str.Replace('H', 'j'));
Console.WriteLine("string(Substring(2, 2)): " + str.Substring(2, 2));
Console.WriteLine("string.Trim(): " + str.Trim());
String name = "Bob";
double value = 123.456;
Console.WriteLine(String.Format("{0} earned {1:$0.00}", name, value));
}
}
Output
string: Hello
string.ToLower(): hello
string.ToUpper(): HELLO
string.IndexOf('e'): 1
string.Length: 5
string.Replace('H', 'j'): jello
string(Substring(2, 2)): ll
string.Trim(): Hello
Bob earned $123.46
Files
// This program demonstrates reading a text file with exception handling.
// References:
// https://en.wikibooks.org/wiki/C_Sharp_Programming
using System;
public class Files
{
public static void Main(String[] args)
{
string FILENAME = "temperatures.txt";
ReadFile(FILENAME);
}
private static void ReadFile(string filename)
{
System.IO.StreamReader file;
string line;
try
{
using (file = System.IO.File.OpenText(filename))
{
while (true)
{
line = file.ReadLine();
if (line == null)
{
break;
}
Console.WriteLine(line);
}
}
}
catch(Exception exception)
{
Console.WriteLine("Error reading " + filename);
Console.WriteLine(exception.Message);
}
}
}
Output
Celsius,Fahrenheit 0,32 10,50 20,68 ... 80,176 90,194 100,212
