Archive for the ‘C#’ Category.
August 28, 2013, 7:12 pm
Here is an example of using enum with a tryParse. The program asks the user to enter a new state. The tryParse then attempts to convert the input into a enum.
// define current state
MyState currentState = MyState.off;
// get value from user
Console.WriteLine("Please enter the new state");
string input = Console.ReadLine();
if (Enum.TryParse(input, out currentState) == false)
{
Console.WriteLine("Unable to compute input");
}
Console.WriteLine("Current state " + currentState);
Console.WriteLine("=== Finished ===");
Console.ReadLine();
}
enum MyState
{
on,
off,
idle
}
August 28, 2013, 5:43 pm
Add seven days to the current time.
DateTime start = DateTime.Now;
Console.WriteLine("Start date = " + start.ToString("dd/MM/yyyy hh:mm:ss"));
DateTime end = start.AddDays(7);
Console.WriteLine("End date = " + end.ToString("dd/MM/yyyy hh:mm:ss"));
Other methods for defining a DateTime object
DateTime start = DateTime.Parse("23/01/1984 01:02:03");
DateTime start = new DateTime(1984, 01, 23, 01, 02, 03);
August 28, 2013, 5:30 pm
A simple example of using the StringBuilder to concat strings.
StringBuilder mySB = new StringBuilder();
mySB.Append("line 1");
mySB.Append("line 2");
mySB.Append("line 3");
Console.WriteLine(mySB.ToString());
August 28, 2013, 5:26 pm
Below is an example of using string formating to print a time
int h = 12;
int m = 13;
int s = 14;
string myString = string.Format("{0}:{1}:{2}", h, m, s);
Console.WriteLine(myString);
To format a number to two decimal places, you could use the string format.
double s = 14.123;
string myString = string.Format("{0:0.00}", s);
Console.WriteLine(myString);
August 28, 2013, 5:16 pm
Reading a text file line by line in C#. Dont forget to include using System.IO;
StreamReader myReader = new StreamReader(@"c:\test.txt");
string line = "";
while (line != null)
{
line = myReader.ReadLine();
Console.WriteLine(line);
}
You can read all the text within a file using the ReadAllText function.
string filename = Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments) + @"\test.txt";
string content = File.ReadAllText(filename);
MessageBox.Show(content);
August 28, 2013, 5:12 pm
Explicit Conversion of a string to Integer, sometimes known as cast.
string myString = "7";
int myInt = int.Parse(myString);
Console.WriteLine(myInt);
The above code will fail if the string can not be converted to a integer. For example if myString=”Seven”, the code would fail. To avoid this problem use TryParse.
string myString = "Seven";
int myInt = 0;
if (int.TryParse(myString, out myInt) == true)
{
Console.WriteLine("String converted");
}
else
{
Console.WriteLine("String NOT converted");
}
Console.WriteLine(myInt);
January 18, 2012, 11:27 pm
This function dowloads the html content of a webpage and returns the content as a string.
public static string GetWebPageAsString(string url) {
HttpWebRequest httpWebRequest =(HttpWebRequest)WebRequest.Create(url);
HttpWebResponse httpWebResponse = (HttpWebResponse)httpWebRequest.GetResponse();
Stream stream = httpWebResponse.GetResponseStream();
StreamReader streamReader = new StreamReader(stream, Encoding.ASCII);
return streamReader.ReadToEnd();
}
January 18, 2012, 11:23 pm
This function will Recursively delete all files and folders.
private void DeleteAllFiles(string sPath)
{
foreach(string strFile in Directory.GetFiles(sPath))
{
File.Delete(strFile);
}
foreach (string strDir in Directory.GetDirectories(sPath))
{
DeleteAllFiles(strDir);
}
Directory.Delete(sPath);
}
January 18, 2012, 11:16 pm
The code example below creates an autocompleting textbox, with the possible values Andy, Andrew, Dylan and Kyle.
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
namespace autoComplete
{
public partial class Form1 : Form
{
AutoCompleteStringCollection nameCollection = new AutoCompleteStringCollection();
public Form1()
{
InitializeComponent();
}
private void Form1_Load(object sender, EventArgs e)
{
nameCollection.Add("Andy");
nameCollection.Add("Andrew");
nameCollection.Add("Dylan");
nameCollection.Add("Kyle");
txtName.AutoCompleteMode = AutoCompleteMode.Suggest;
txtName.AutoCompleteSource = AutoCompleteSource.CustomSource;
txtName.AutoCompleteCustomSource = nameCollection;
}
}
}
January 18, 2012, 11:12 pm
Create an ArrayList and add three elements.
using System.Collections;
class Program
{
static void Main()
{
ArrayList list = new ArrayList();
list.Add("One");
list.Add("Two");
list.Add("Three");
}
}