C# Reference

WebForms

TextBoxes

You can restrict length using maxlength property unless you set property textmode=multiline then the textbox is output in HTML as a textarea for which there is no maxlength property. Instead just created javascript function called from the textbox called ontextchanged; to access a javascript function from a server control you must input this code in the c#

if(!Page.IsPostBack)

{

txtDescription.Attributes.Add( "OnKeyUp","checklen()");

}

DropDownList

Properties

Properties like visible in Design Properties Manager is Capatalized Visible = False;

But in c# code false is lowercase

Application

Application.DoEvents(); // processes previous instructions (like changing a label to In Process….)

Arrays

string[] myStrings = new string[3];

string[] Words = strOriginalValue.Split('.');

(In C# you cannot split on a string only a char-so only a single character, you can do a replace on a string and change it to a char(like a |))

Array List

ArrayList arrList = new ArrayList(50);

arrList.Add("http://www.hub.slb.com/Docs/NSA_TZ_Data_Sales/lafourche.pdf");

arrList.Count

to bind to DropDownList

ddlProjectName.DataSource=alProj;

to get back out

for(int i2=0;i2<alBad.Count;i2++)

{

string tester = alBad[2].ToString();

twB.Write (alBad[i2].ToString()+ "\r\n");

}

Date

Current Date/Time - DateTime.Now.ToString()

Current Date - DateTime.Now.ToShortDateString();

DateTime dtstr = DateTime.Now;

TimeSpan diff = dtstr.Subtract(fiFile.CreationTime);

dttmCompare2 = Convert.ToDateTime(myDataReader5["timedate"].ToString());

tmspCompare = dttmCompare.Subtract(dttmCompare2);

intDiff = tmspCompare.TotalMinutes;

if (intDiff > 5)

Database Access

using System.Data.SqlClient;

SqlConnection myConnection;

string strSqlConnect = "server=database;database=mms_data;uid=sa;pwd=19wazee";

myConnection = new SqlConnection(strSqlConnect);

myConnection.Open();

SqlCommand myCommandddl2;

string sql = " select * from tablename";

myCommandddl2 = new SqlCommand(sql,myConnection);

SqlDataReader myDataReaderddl3 = myCommandddl2.ExecuteReader();

while (!myDataReaderddl3.Read())

{

deleteString =myDataReaderddl3["plan_ctrl_num"].ToString();

}

-----------------------------------------------------------

string selectSql2 = "SELECT count(*) FROM maptester” SqlCommand myCommand2;

myCommand2 = new SqlCommand(selectSql2,myConnection);

string myData2 = myCommand2.ExecuteScalar().ToString();

----------------------------------------------------------

myConnection.Open();

strSql = "update TblRequestTopFive set RequestSubmitted = '1' where requestClientName = '" + sName + "'";

SqlCommand comCommand2 = new SqlCommand(strSql,myConnection);

comCommand2.ExecuteNonQuery();

------------------------------------------------------------

DataGrid

private void DataGrid4_ItemDataBound(object sender, System.Web.UI.WebControls.DataGridItemEventArgs e)

{

// In Recent Results Turn rows red if the map is down.

if (e.Item.ItemType == ListItemType.AlternatingItem || e.Item.ItemType == ListItemType.Item || e.Item.ItemType == ListItemType.EditItem || e.Item.ItemType == ListItemType.SelectedItem)

{

string vworked = DataBinder.Eval(e.Item.DataItem, "worked", "{0}");

if(vworked == "NO")

((Label) e.Item.FindControl("Label7")).BackColor = Color.Red;

Event Handling

Make sure bind is in !postback or else event handler won’t work.

Exception Handling

Try

{}

catch(Exception vE)

{

string vExceptMsg;

vExceptMsg = vE.ToString();

}

private class cException : System.Exception

{

private string m_Message = "";

public cException(string message)

{

m_Message = message;

}

public override string ToString()

{

return m_Message;

}

}

Email

using System.Web.Mail;

string sTo = "ccupp@petroweb.com";

string sFrom = "ccupp@petroweb.com";

string sSubject = "The C# Map program failed somewhere ";

string sBody = "The C# Map program failed somewhere " + vStatusMsg;

SmtpMail.SmtpServer = "MailBox2";

SmtpMail.Send(sFrom,sTo,sSubject,sBody);

Or

MailMessage nmMessage = new MailMessage();

nmMessage.To = "ccupp@petroweb.com, pwalsh@petroweb.com";

nmMessage.From = "pwalsh@petroweb.com";

nmMessage.Subject = "How does this look... petroWEB map.";

nmMessage.Body = sbBody.ToString();

nmMessage.BodyFormat = MailFormat.Html;

SmtpMail.SmtpServer = "MailBox2";

SmtpMail.Send(nmMessage);

Switch

switch(myChoice)
{
case "A":      

Console.WriteLine("You wish to add an address.");
break;

default:
Console.WriteLine("{0} is not a valid choice", myChoice);
break;
}

ForEach

string[] names = {"Cheryl", "Joe", "Matt", "Robert"};

foreach (string person in names)
{
Console.WriteLine("{0} ", person);
   }

XML

using System.Xml;

//Instanciate an XMLDocument object

XmlDocument doc = new XmlDocument();

//Load the doc (parses at the same time apparently)

doc.Load(reader);Selectnodes()

XmlDocument doc = ReadXMLFromString(strRequest);

XmlNodeList nodes = doc.GetElementsByTagName("ENVELOPE");

File Objects

using System.IO;

DirectoryInfo()

FileInfo()

foreach(FileInfo fiFile in dirDirect.GetFiles())

{

for(z=0;z<arrFileList.Count;z++)

{

fiFile.MoveTo(strNewPath + arrFileList[z]);

}

}

TextReader tr = new StreamReader(fileloc + filenm);

while (tr.Peek()>-1) //if line exists

{

sLine = tr.ReadLine();

}

//close the stream

tr.Close();

TextWriter tw = new StreamWriter("../../testing.txt");

tw.Write (sb.ToString());

tw.Close();

WebRequest vReq = null;

WebResponse vResult = null;

StreamReader vStreamReader = null;

Stream vReceiveStream = null;

Encoding vEncoding = Encoding.GetEncoding("UTF-8");

vReq = WebRequest.Create(strURL);

vReq.Method = "GET";

vResult = vReq.GetResponse();

vReceiveStream = vResult.GetResponseStream();

vStreamReader = new StreamReader(vReceiveStream, vEncoding);

strAxlResponse = vStreamReader.ReadToEnd();

vResult.Close();

vStreamReader.Close();

String – StringBuilder

string bodytext = "", line;

StringBuilder noString = new StringBuilder();

noString.Append( "No List \r\n");

sb.AppendFormat("L,\"{0}\",\"{1}\",{2}\r\n", sName.Trim(), sName.Trim(), namecount);

References

Must add references if not available (ie. System.Web.Mail for Console apps)

Just right click add reference

For web references for WebServices.

Regular Expressions

string[] arCols = Regex.Split(sLineBig,"<td");

if(Regex.IsMatch(arCols[y],"table"))

split – regex can split on a string where string can only do it on a char

This is important for parsing HTML

HttpWebRequest – HttpWebResponse

//simpler way

string strURL = "http://www2.petroweb.com/UpaaLogin.aspx?ReturnUrl=%2fDefault.aspx";

HttpWebRequest HttpWReq = (HttpWebRequest)WebRequest.Create(strURL);

/HttpWebRequest HttpWReq = (HttpWebRequest)WebRequest.Create("http://www.cuppcondo.com");

HttpWebResponse HttpWResp = (HttpWebResponse)HttpWReq.GetResponse();

string stringResult2;

using (StreamReader sR2 = new StreamReader(HttpWResp.GetResponseStream()))

{

stringResult2 = sR2.ReadToEnd();

sR2.Close();

}// Insert code that uses the response object.

HttpWResp.Close();

stringResult2 +="";

if(stringResult2.IndexOf("password")>0)

// end of simple….

HttpWebRequest httprequest;

HttpWebResponse httpresponse;

Uri responseUri = null, requestUri;

StreamReader bodyreader;

requestUri = new Uri(arrList[x].ToString());

//create the web request.

httprequest = (HttpWebRequest) WebRequest.Create(requestUri);

//fill in the properties of the request. All properties

//are optional

//allow auto redirects from redirect headers

httprequest.AllowAutoRedirect=true;

//maximum of 10 auto redirects

httprequest.MaximumAutomaticRedirections=10;

//use the GET method

httprequest.Method="GET";

//use HTTP/1.0

httprequest.ProtocolVersion=new Version(1,0);

//30 second timeout for request

httprequest.Timeout=(int) new TimeSpan(0,0,20).TotalMilliseconds;

//give the crawler a name.

httprequest.UserAgent="Mozilla/3.0 (compatible; My Browser/1.0)";

//retrieve the response from the requestUri.

httpresponse = (HttpWebResponse) httprequest.GetResponse();

//remember the url that responded because it may not

//be the same as the input url because of the autoredirect

//property setting above.

responseUri = httpresponse.ResponseUri;

//get the body stream of the requested page.

responsestream = httpresponse.GetResponseStream();

if (responsestream != null)

{

//read the stream and build it into a string

//representing the body of the web page.

bodyreader = new StreamReader(responsestream);

//loop the body, reading line by line

while((line=bodyreader.ReadLine())!=null)

{

bodytext+=line+"\r\n";

}

//close the body stream

bodyreader.Close();

//cleanup

bodyreader = null;

}

//close response which cleans up the socket used to

//retrieve the page.

httpresponse.Close();

//cleanup

httpresponse = null;

httprequest = null;

WebServices

private localhost.Service1 RS;

localhost.Service1 RS1 = new localhost.Service1();

RS1.Url = "http://216.87.66.115/newMaptesterService/Service1.asmx";

RS1.WriteToMaptester(strInsertSQL);