How to evaluate 2 strings in ASP.NET C# WebMethod return in JQuery

Question

I have a WebMethod that updates an SQL database based on parameters passed from a ASP.NET button. On success the WebMethod returns the state and is used to show or hide a div. However the Javascript condition always evaluates as "Yes" even though "No" is passed back.

Control:

<telerik:RadButton
        TabIndex="1"
        ID="Updated"
        runat="server"
        ButtonType="ToggleButton"
        ToggleType="Checkbox"
        AutoPostBack="false"
        OnClientToggleStateChanged="ButtonSelect"
        CommandArgument="Updated" 
        CommandName="Updated">
             <ToggleStates>
                  <telerik:RadButtonToggleState
                          Text="No" 
                          PrimaryIconCssClass="rbToggleRadio"> 
             </telerik:RadButtonToggleState>
             <telerik:RadButtonToggleState
                 Text="Yes" 
                 PrimaryIconCssClass="rbToggleRadioChecked"> 
             </telerik:RadButtonToggleState>
        </ToggleStates>
   </telerik:RadButton>

JQuery:

<script type="text/javascript">
    function ButtonSelect(button, args) {
        var state = args.get_currentToggleState().get_text();
        var whois = args.get_commandName();

        PageMethods.ButtonWebMethod(state, whois, onSucess, onError);

        //edited Stack Overflow Quetion here to == from =:
        function onSucess(returnstate) {
            if ((whois == "Updated") && (returnState == "Yes"))
            {
                $("#updateChoiceDIV").show();
                alert(returnstate + "Yep");
            }
            else if ((whois == "Updated") && (returnState == "No"))
            {
                $("#updateChoiceDIV").hide();
                alert(returnstate + "Nope");
            }
        }
        function onError(result) {
            alert('Cannot process your request at the moment, please try later.');
        }
    }
</script>

WebMethod:

[WebMethod]
[ScriptMethod(UseHttpGet = true)]
public static string ButtonWebMethod(string state, string whois)
{
    string returnState = state;
    HttpContext.Current.Session["FieldName"] = whois;
    if (state == "Yes")
    {
        HttpContext.Current.Session["" + whois + ""] = "True";
    }
    else if (state == "No")
    {
        HttpContext.Current.Session["" + whois + ""] = "False";
    }
    string strConnString = WebConfigurationManager.
                                ConnectionStrings["gatorConnectionString"].
                                ConnectionString;
    try
    {
        string sql = "UPDATE [User] SET " + 
                        HttpContext.Current.Session["FieldName"] + "='" + 
                        HttpContext.Current.Session["" + whois + ""] + 
                        "' WHERE Id = '" + HttpContext.Current.Session["newID"] + 
                        "' ";
        using (SqlConnection conn = new SqlConnection(strConnString))
        {
            conn.Open();
            using (SqlCommand cmd = new SqlCommand(sql, conn))
            {
                cmd.ExecuteNonQuery();
                conn.Close();
            }
        }
    }
    catch (SqlException ex)
    {
        string msg = "Update Error:";
        msg += ex.Message;
    }
    return returnState;
}

And yes I'm not great at Javascript so be kind....

Answer 1

Alright, so a couple issues were found through the comments.

• Assignment (=) will typically return as true

This is because the result of an assignment is the value you set to it, which is typically not a falsy value.

var x;
var y;

if (x = 1) { console.log(true); }
if (y = 0) {} else { console.log(false); }

The correct way to compare values is to use === or ==. If you expect, and require, that the two variables have the same type (compairing string to string or number to number) then you should use the === version. If, however, you wish to allow the logic to coerce the values to be the same type (such as compairing 1 to "1") then you should use == and javascript will coerce them to the same type before compairing.

• returnstate != returnState

The second issue was that the argument returnstate was being provided to the function, however the inner logic was referencing returnState which didn't match the case of the previous variable, so it would have been undefined for all the expressions.