C# & Dot Net: 2012

Tuesday, October 2, 2012

Jquery: How to use index()

.index()- returns an integer indicating the position of the passed element relative to the original collection.
-1 means selector or element not found.

Three way to use index()
1.index()

2..index( selector )
selector A selector representing a jQuery collection in which to look for an element.
3..index( element )
element The DOM element or first element within the jQuery object to look for.

Note : Start index is 0(Zero).

more detail- http://api.jquery.com/index

Example

<html>
<head>
  <style>div { font-weight: bold; color: #090; }</style>
  <script src="http://code.jquery.com/jquery-latest.js"></script>
</head>
<body>
  <ul>
  <li id="foo">foo</li>
  <li id="bar">bar</li>
  <li id="baz">baz</li>
</ul>
<div></div>
 <script>

    var listItem = $('#bar');
    $('div').html( 'Index: ' + $('li').index(listItem) );

 </script>
</body>
</html>

Output Demo

Index: 1

Wednesday, August 29, 2012

JQuery:preventDefault() method will do.


e.preventDefault() is the key method, to disable the default operations to proceed further. We first stop the event from further bubbling up to other parent controls and put any custom logic.

@"e" is a event.


Example:
$('#<%=textbox.ClientID%>').bind('cut copy paste',
function (e) {
e.preventDefault();
alert("Cut / Copy / Paste are not allowed.");

});

Tuesday, August 28, 2012

MVC: set Default value in Html.TextboxFor Helper In Asp.Net MVC 2

Html.TextBoxFor in MVC 2 doesn't allow the setting of the value property using the object html attributes.
syntax - 
<%= Html.TextBoxFor(model => model.city, new { maxlength = "40" })%>

If you need to set a default value on a textbox field, you need to use the old 

syntax - 
<%= Html.TextBox("city", "New Delhi", new { maxlength = "40" })%>

Thursday, March 1, 2012

Generic function call

public class clsGeneric
{
public void show<T>(T value)
{
Type t = typeof(T);
Console.WriteLine(t.Name + ":" + value);
}
}

class Program
{
static void Main(string[] args)
{
clsGeneric ng;
ng = new clsGeneric();
int a = 10;
ng.show(a);
string b = "SS";
ng.show(b);

Console.WriteLine("Press any key to close........");
Console.ReadKey();
}
}

OUTPUT
----------------------------
Int32:10
String:SS
Press any key to close........

use global variable with same name of Local variable

public class Demo1
{
int a = 10;
public void ff()
{
int a = 11;
Console.WriteLine("a={0}", this.a);
}

class Program
{
static void Main(string[] args)
{
Demo1 ng = new Demo1();
ng.ff();

Console.WriteLine("Press any key to close........");
Console.ReadKey();

}
}

Output:
-----------------------------------
a=10
Press any key to close........
-----------------------------------

Tuesday, February 14, 2012

Bind generic dictionary collection to combobox

Dictionary<string, string> DicSearch;
DicSearch = new Dictionary<string, string>();
DicSearch.Add("1", "Mohit");
DicSearch.Add("2", "Agrawal");

cboSearch.DataSource = new BindingSource(DicSearch, null);
cboSearch.DisplayMember = "value";
cboSearch.ValueMember = "key";
DicSearch = null;

Tuesday, February 7, 2012

Regular Expression

Regular Express class and validation done himself.

SqlCommand Query based on parameters

SqlCommand command = new SqlCommand();
command.CommandText = "SELECT * FROM Emplyoee emp WHERE emp.Name=@EmpName";
command.Parameters.Add(new SqlParameter(" @EmpName", 50));

// Execute the SQL Server command...
SqlDataReader reader = command.ExecuteReader();
DataTable tblemplyee = new DataTable();
tblemplyee.Load(reader);

foreach (DataRow rowProduct in tblemplyee.Rows)
{
// Use the data...
}

NOTE: This is a good way to block SQL injection

"" vs String.Empty

String.Empty is faster than "" because it doesn't create a new string object instance. Creating new instances brings penalties on both execution speed and memory usage.

Example:

// Slowest

str1 == "";

// Slow

str1.Equals(" ") == false

//Fast

str1 == String.Empty

// Fastest

str1.Equals(String.Empty) == false

Monday, January 23, 2012

Working with Nullable Types

******************* Type 1 ***********************
int iUnits;
int iStock ;
if (iStock== null)
{
      iUnits= 0;
   }
else
{
     iUnits= (int)iStock;
}

******************* Type 2 ***********************
// using the coalesce operator, ??,
    int iUnits= iStock ?? 0;
The coalesce operator works like this: if the first value (left hand side) is null, then C# evaluates the second expression (right hand side).

Declare Null datetime variable

****************** Type 1 *********************
System.Nullable<DateTime> dt;
dt = null;

****************** Type 2 *********************
DateTime? dt1;
dt1 = null;

How to Use foreach in Multiple classes

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Collections;

namespace Indexer
{

public class NameDetail
{
public string FirstName { get; set; }
public string MiddleName{ get; set; }
public string LastName { get; set; }
public string FullName
{
get
{
String strFullname="";
if (string.IsNullOrEmpty(FirstName) == false )
{
strFullname = FirstName;
}
if (string.IsNullOrEmpty(MiddleName) == false)
{
strFullname += MiddleName;
}
if (string.IsNullOrEmpty(LastName) == false)
{
strFullname += LastName;
}
return strFullname.Trim();
}

}
}

public class Name: IDisposable, IEnumerable, IEnumerator
{
List arrPos = new List();
public int count { get ;set ;}
private int Position = -1; // This is for Ienum interface

public NameDetail this[int pos]
{
get
{
try
{
return arrPos[pos];
}
catch(Exception ex)
{
throw new Exception(ex.Message);
}
}
set
{
if (arrPos.Count <= pos)
{
arrPos.Insert(pos, value);
count = arrPos.Count;
}
else
{
throw new Exception("No Index postiion");
}
}
}
#region IDisposable
public void Dispose()
{
arrPos = null;
}
#endregion IDisposable

//**********************************************************
//********************* Use For Each in object *************
//*********************************************************
#region IEnumerable Members
public IEnumerator GetEnumerator()
{
return (IEnumerator)this;
}
public bool MoveNext()
{
if (Position < arrPos.Count - 1)
{
++Position;
return true;
}
return false;
}
public void Reset()
{
Position =-1;
}
public object Current
{
get
{
return arrPos[Position];
}
}
#endregion
}

class Program
{
static void Main(string[] args)
{
Name a = new Name();
NameDetail ND ;
ND = new NameDetail();
ND.FirstName = "Mohit";
ND.LastName = "Agrawal";
a[0] = ND;
ND = new NameDetail();
ND.FirstName = "aaa";
a[1] = ND;

foreach (NameDetail n in a)
{
Console.WriteLine(n.FirstName );
Console.WriteLine(n.MiddleName);
Console.WriteLine(n.LastName );
Console.WriteLine(n.FullName);
}
Console.ReadKey();
a.Dispose();
a = null;
ND = null;
}
}
}

C# & Dot Net