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Monday, 17 April 2017

Difference between var and dynamic in C#

var	dynamic
Statically typed – This means the type of variable declared is decided by the compiler at compile time.	Dynamically typed - This means the type of variable declared is decided by the compiler at runtime time.
Need to initialize at the time of declaration. e.g., var str=”I am a string”; Looking at the value assigned to the variable str, the compiler will treat the variable str as string.	No need to initialize at the time of declaration. e.g., dynamic str; str=”I am a string”; //Works fine and compiles str=2; //Works fine and compiles
Errors are caught at compile time. Since the compiler knows about the type and the methods and properties of the type at the compile time itself	Errors are caught at runtime Since the compiler comes to about the type and the methods and properties of the type at the run time.
Visual Studio shows intellisense since the type of variable assigned is known to compiler.	Intellisense is not available since the type and its related methods and properties can be known at run time only
e.g., var obj1; will throw a compile error since the variable is not initialized. The compiler needs that this variable should be initialized so that it can infer a type from the value.	e.g., dynamic obj1; will compile;
e.g. var obj1=1; will compile var obj1=” I am a string”; will throw error since the compiler has already decided that the type of obj1 is System.Int32 when the value 1 was assigned to it. Now assigning a string value to it violates the type safety.	e.g. dynamic obj1=1; will compile and run dynamic obj1=” I am a string”; will compile and run since the compiler creates the type for obj1 as System.Int32 and then recreates the type as string when the value “I am a string” was assigned to it. This code will work fine.

Thursday, 30 June 2016

How to Consume RESTFul Service by passing complex type Object/parameters in wcf post method in C# Asp.Net

Firstly you need create a class if you want to send a complex object in WCF REST service request .Here is sample:

public class Artist

{

public string SearchArtist { get; set; }

public string State { get; set; }

public string Suburb { get; set; }

public string Postcode { get; set; }

public DateTime DateForm { get; set; }

public DateTime? DateTo { get; set; }

public int TotalEventsToReturn { get; set; }

}

Now import the following namespace in your project

using System.Web.Script.Serialization;

and just copy and paste below code in your project

private void getArtist()

{

//Create object of Artist class

Artist artist = new Artist();

artist.DateForm = DateTime.UtcNow;

artist.Postcode = "2000";

artist.SearchArtist = "artistname";

artist.State = "NSW";

artist.Suburb = "Sydney";

artist.TotalEventsToReturn = 80;

//If you want to add root name as well in your Json request then you need to write below code as well otherwise you can skip this code

dynamic collectionWrapper = new

{

artist = artist

};

//Create JavaScriptSerializer object to serialize artist object to Json string

JavaScriptSerializer js = new JavaScriptSerializer();

// Json string after serialization

string json = js.Serialize(collectionWrapper);

// Make a http web request with URL

var httpWebRequest = (HttpWebRequest)WebRequest.Create("http://local.liveguide.com.au/LiveGuideDataAPI.svc/GetArtistEvents");

// Set content type such as Json,Xml for response

httpWebRequest.ContentType = "application/json; charset=utf-8";

httpWebRequest.Method = "POST";

using (var streamWriter = new StreamWriter(httpWebRequest.GetRequestStream()))

{

streamWriter.Write(json);

streamWriter.Flush();

}

//Set header such as AccessToken or API Key, these are the confidential information so need to send in Header. If you don’t need to send any such information than simply remove this code

httpWebRequest.Headers.Add("AccessToken", "5347-c48b-4803-9056-6869");

var httpResponse = (HttpWebResponse)httpWebRequest.GetResponse();

using (var streamReader = new StreamReader(httpResponse.GetResponseStream()))

{

// Result as response for WCF Service

var result = streamReader.ReadToEnd();

}

Noteè If you are getting compile time error ‘One or more types required to compile a dynamic expression cannot be found. Are you missing a reference?’ then you just need reference of Microsoft.CSharp from assembly

How to Pass JavaScript object from jQuery AJAX post method in WCF REST Service

Now copy and paste below code in your page. You have to change URL and Artist object according to your need.

$("#btnEvent").live("click", function () {

debugger;

var myDate = '2016.06.26' //set from date here

var jsondate = convertToJSONDate(myDate)

var artist = {}; // object for request

artist.SearchArtist = "t"; //Artist to be search

artist.State = "NSW";

artist.Suburb = "Sydney";

artist.Postcode = 2000;

artist.DateForm = convertToJSONDate(myDate) // convert from date to json

artist.TotalEventsToReturn = 80;

var jsonstng = "{\"artist\":" + JSON.stringify(artist) + "}"; // add root name if you need

//Post request to Live Guide Service

$.ajax({

type: "POST",

contentType: "application/json; charset=utf-8",

url: 'http://local.abc.com.au/AbcDataAPI.svc/GetArtistEvents',//you can set local host

headers: { 'AccessToken': '5347-c48b-4803-9056-6869' },//your API key

data: jsonstng,

dataType: "json",

processData: false,

success: function(result) {

for (var i = 0; i < result.GetArtistEventsResult.Events.length; i++) {

$("#Events").append("<tr><td>" + result.GetArtistEventsResult.Events[i].Name + "</td><td>" + result.GetArtistEventsResult.Events[i].Artists + "</td>");

}

error: function (result) {

alert(result);

}

});

// Function to convert javascript date to json date

function convertToJSONDate(myDate) {

var dt = new Date(myDate);

var newDate = new Date(Date.UTC(dt.getFullYear(), dt.getMonth(), dt.getDate(), dt.getHours(), dt.getMinutes(), dt.getSeconds(), dt.getMilliseconds()));

return '/Date(' + newDate.getTime() + ')/';

}

</script>

// Code Sample for body section

<div>

<tr>

<th>Artists</th>

</tr>

</table>

</div>

</form>