calling webservice with parameter

Question

Hi,

I am trying to call webservice method to get the string, but nothing happening, it wont display it in the label.

Can u help?? plz

using System;
using System.Collections.Generic;
using System.Data;
using System.Data.SqlClient;
using System.Linq;
using System.Web;
using System.Web.Script.Serialization;
using System.Web.Script.Services;
using System.Web.Services;

namespace WebService
{
/// Summary description for Service1
/// </summary>
[WebService(Namespace = "http://tempuri.org/")]
[WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)]
[System.ComponentModel.ToolboxItem(false)]
// To allow this Web Service to be called from script, using ASP.NET AJAX, uncomment the following line.

//[System.Web.Script.Services.ScriptService]
public class Service1 : System.Web.Services.WebService
{

[WebMethod]
public string GetCurrencyRate(string FromCurrencyCode, string ToCurrencyCode)
{

string Rate = "";

//Create connection
SqlConnection con = new SqlConnection(@"Data Source=Comp1;Initial Catalog=CurrencyExchange;Integrated Security=True;");
//Instantiate connection
SqlDataReader rdr = null;

try
{

con.Open();

SqlCommand cmd = new SqlCommand("spGetRate", con);
cmd.CommandType = CommandType.StoredProcedure;
cmd.Parameters.Add(new SqlParameter("@FromCurrencyCode", SqlDbType.Char)).Value = FromCurrencyCode;
cmd.Parameters.Add(new SqlParameter("@ToCurrencyCode", SqlDbType.Char)).Value = ToCurrencyCode;

rdr = cmd.ExecuteReader();

while (rdr.Read())
{
Rate = rdr["Rate"].ToString();
}

//Close Connection
rdr.Close();
con.Close();

return Rate;

}

finally
{

if (rdr != null)
{
rdr.Close();
}

if (con != null)
{
con.Close();
}
}

}

using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;

namespace WebService
{
public partial class Dafault : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{

}

protected void Button1_Click(object sender, EventArgs e)
{

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

string sGetValue = CallWebService.GetCurrencyRate(ddlFromCurrency.SelectedItem.Text, ddlToCurrency.SelectedItem.Text);
lbDisplay.Text = sGetValue;

}
}
}

<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="Default.aspx.cs" Inherits="WebService.Default" %>

<!DOCTYPE html>

<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title></title>

</head>
<body>
<form id="form1" runat="server">

<div>

<asp:DropDownList ID="ddlFromCurrency" runat="server" DataSourceID="ObjectDataSource1" DataTextField="CurrencyName" DataValueField="CurrencyName">
</asp:DropDownList>

<asp:DropDownList ID="ddlToCurrency" runat="server" DataSourceID="ObjectDataSource1" DataTextField="CurrencyName" DataValueField="CurrencyName" Height="16px">
</asp:DropDownList>
<asp:ObjectDataSource ID="ObjectDataSource1" runat="server" SelectMethod="LoadCurrency" TypeName="WebService.Service1"></asp:ObjectDataSource>
<br />
<br />
<br />

<br />
<br />

<asp:Button ID="Button1" runat="server" OnClick="Button1_Click" Text="Button" />
<br />
<br />
<asp:Label ID="lbDisplay" runat="server"</asp:Label>

<br />
<br />
<div id="output">
</div>
</div>
</form>
</body>
</html>

Guest User · Answer

Hi, I have it solved, my webservice was expecting char(3) string for its method and I was sending selected value from ddlist which was different string. thanks

Sakthikumar Thanavel · Answer

Where you form this string format. try to assign some string message to Rate variable like Rate="Error". you can find problem.

Guest User · Answer

Hi, I did uncomment System.Web.Script.Services.ScriptService and put return Rate inside try and finnaly but non of them help. I can return hardcoded string eg. return string.Format("The rate is: {0}", Rate); The webservice return string and value correct, but application return only (The rate is: )

Sakthikumar Thanavel · Answer

Hi! You only return the value inside try block. 1.try to put the return statement outside of try catch or both try and catch. try { return value; } catch(Exception ex) { return value; } 2. put return statement in finally block. [WebMethod] public string GetCurrencyRate(string FromCurrencyCode, string ToCurrencyCode) { string Rate = ""; //Create connection SqlConnection con = new SqlConnection(@"Data Source=Comp1;Initial Catalog=CurrencyExchange;Integrated Security=True;"); //Instantiate connection SqlDataReader rdr = null; try { con.Open(); SqlCommand cmd = new SqlCommand("spGetRate", con); cmd.CommandType = CommandType.StoredProcedure; cmd.Parameters.Add(new SqlParameter("@FromCurrencyCode", SqlDbType.Char)).Value = FromCurrencyCode; cmd.Parameters.Add(new SqlParameter("@ToCurrencyCode", SqlDbType.Char)).Value = ToCurrencyCode; rdr = cmd.ExecuteReader(); while (rdr.Read()) { Rate = rdr["Rate"].ToString(); } //Close Connection rdr.Close(); con.Close(); return Rate; } finally { if (rdr != null) { rdr.Close(); } if (con != null) { con.Close(); } } Note: Your method will throw compile time error. because the method did not return string except the try block.

Anubhav Chaudhary · Answer

There is a basic mistake in your code which is done by nearly all the programmers, //[System.Web.Script.Services.ScriptService] This line is commented at the top of your code, uncomment this code otherwise no Web Method would be hit.

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Answers (5)