How to create and use Web service ? - The simplest way

Introduction

Here by, i have created a program to create and consume (call) the web service in a simplest way. Often, i have seen people stumbling on web services (even i used to), but after trying it in my own way i have enough confidence to work with it.

Steps to Create Web Service

• Select File menu option > Create new web site > Select template “ASP .Net Web Service”
• This will add WebService.asmx and it will add in App_code > WebService.cs / WebService.vb
• In WebService.cs / WebService.vb, implement your Web Method(s).

Consuming (Calling) Web Service

Web Services can be consumed in 2 ways :

1. Select Project / Web site > right-click > Add Web Reference

Follow the wizard. If you select option “Web service in this solution”, it will do following things

• Creates App_WebReferences folder
• Create localhost having 2 files – .disco & .wsdl
• Then write following code in .aspx > Button click event :
• [Here, WebService is the name of the web service.]

//**************USING ADD WEB REFERENCE************************

localhost.WebService objWebService = new localhost.WebService();
Response.Write(objWebService.AddTwoNumbers(Convert.ToInt16(txtNum1.Value), Convert.ToInt16(txtNum2.Value)));

   2. By coding (in .aspx’s Button Click event)

protected void btnSubmit_Click(object sender, EventArgs e)
{
//*************************BY CODE******************************
XmlDocument xmlDoc = new XmlDocument();
MSXML2.XMLHTTP xmlHTTP;
DataSet MyDS;
//CREATING SOAP ENVELOPE
string soap =
@"

xmlns:xsd=""http://www.w3.org/2001/XMLSchema"" 
xmlns:soap=""http://schemas.xmlsoap.org/soap/envelope/"">


" + txtNum1.Value.ToString();
soap += @"";
soap += @"" + txtNum2.Value.ToString();
soap += @"


";
try
{
//SET WEB SERVICE PATH, CAN ALSO BE READ FROM FILE
string WSPath = "http://localhost:2598/RnD-CSharp-WebSite2008/Web%20service/WebService.asmx"; //this can be any path where you Web service resides
//GENERATE REQUEST
xmlHTTP = new MSXML2.XMLHTTP();
xmlHTTP.open("Post", WSPath, false, "", "");
xmlHTTP.setRequestHeader("SOAPAction", "http://tempuri.org/AddTwoNumbers ");
xmlHTTP.setRequestHeader("Content-Type", "text/xml; charset=utf-8");
//MAKING A CALL TO WEB SERVICE
xmlHTTP.send(soap.ToString());
//LOADING RESPONSE OF WEB SERVICE & DISPLAYING TO USER
xmlDoc.LoadXml(xmlHTTP.responseText.ToString());
MyDS = new DataSet();
MyDS.ReadXml(new System.Xml.XmlNodeReader(xmlDoc));
int returnVal = Convert.ToInt16(MyDS.Tables[1].Rows[0][0].ToString());
Response.Write(returnVal);
}
catch (System.Net.WebException ex)
{
throw ex;
}
finally
{
xmlDoc = null;
xmlHTTP = null;
MyDS = null;
}
} //End brace of click event

WEB METHOD written in WebService.cs :

[WebMethod]
public int AddTwoNumbers(string Num1, string Num2)
{
return Convert.ToInt16(Num1) + Convert.ToInt16(Num2);
}

Conclusion

So friends, hows it ? Easy na, now give it a try :) Happy coding buddies !

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by Psmiles18