Error with decimal
<p>My webservice code</p>

<pre><code>[WebService(Namespace = "http://tempuri.org/")]
[WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)]
public class Service : System.Web.Services.WebService
{
    SqlConnection con = new SqlConnection(
        "Server=NOVA-PC;database=totev006;User ID=***;Password =***;");

    public Service () { }

    [WebMethod(Description = "Update return in Bet")]
    public string setReturn(int EventID)
    {
        string sql = "";
        decimal dcm = (decimal)100.5 + (decimal)45.055;
        int BetTypeWinID = 1;
        int BettorID = 1;
        int ins = 0;

        con.Open();
        SqlCommand cmd = new SqlCommand();
        cmd.Connection = con;

        sql = "update bet";
        sql += " set [return] = " + dcm;
        sql += " where event_id = " + EventID;
        sql += " and bet_type_id = " + BetTypeWinID;
        sql += " and bettor_id = " + BettorID;

        cmd.CommandText = sql;
        ins += cmd.ExecuteNonQuery();
        con.Close();
        if (ins &gt; 0)
            return "Ok";
        else
            return "not Ok";
    }
}
</code></pre>

<p>I get exception and this is the callstack:</p>

<pre><code>System.Data.SqlClient.SqlException: Incorrect syntax near &amp;#39;555&amp;#39;.
at System.Data.SqlClient.SqlConnection.OnError(SqlException exception, Boolean breakConnection)
at System.Data.SqlClient.SqlInternalConnection.OnError(SqlException exception, Boolean breakConnection)
at System.Data.SqlClient.TdsParser.ThrowExceptionAndWarning()
at System.Data.SqlClient.TdsParser.Run(RunBehavior runBehavior, SqlCommand cmdHandler, SqlDataReader dataStream, BulkCopySimpleResultSet bulkCopyHandler, TdsParserStateObject stateObj)
at System.Data.SqlClient.SqlCommand.RunExecuteNonQueryTds(String methodName, Boolean async)
at System.Data.SqlClient.SqlCommand.InternalExecuteNonQuery(DbAsyncResult result, String methodName, Boolean sendToPipe)
at System.Data.SqlClient.SqlCommand.ExecuteNonQuery()
at Service.setReturn(Int32 EventID) in e:\Learning\Webservice\demo\webservice\App_Code\Service.cs:line 49
</code></pre>

<p>How to fix this?</p>
