asp.net core verify a model is not null before jquery

Marius Vasile

4y1.4k.NET

I have a query to be executed on a btn click. The problem is that I can't even open the page because the model is null which I know it is innitialy but becomes not null based on a parameter passed later. What I tried is

$(function(){
                $("#btnVer").on("click", function(){
                    if("@(Model.IntrebareClass != null)")
                    {
                        //checkA
                        if($("#rasA").hasClass("colorA") && checkA == "@Model.IntrebareClass.CorectA")
                        {
                            $("#rasA").css("background-color", "green")
                        }

this is a part of the jquery. How do I fix this?

7 Replies

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Marius Vasile4y ago
I manage to fix it by using a JSON call
$.getJSON(`?handler=CorrectDetails&id=${id}`, (data) => {
                    if (!jQuery.isEmptyObject(data)) {

                        //checkA
                        if($("#rasA").hasClass("colorA") && checkA == data.corectA)
                        {
                            $("#rasA").css("background-color", "green");
                        }
                        else if($("#rasA").hasClass("colorA") && checkA != data.corectA)
                        {
                            $("#rasA").css("background-color", "red");
                        }
                        else if($("#rasA").hasClass("colorB") && checkA == data.corectA)
                        {
                            $("#rasA").css("background-color", "gray");
                        }
Sachin Singh4y ago
what if you check with boolean
if($("#rasA").hasClass("colorA") && checkA == Boolean("@Model.IntrebareClass.CorectA") )
Marius Vasile4y ago
Also, the error is on line
if($("#rasA").hasClass("colorA") && checkA == "@Model.IntrebareClass.CorectA")
checkA was assigned true value with
var checkA == true;
and Model.Intrebare.CorectA is the result of a checkbox, true or false
Marius Vasile4y ago
Thank you all for answers, I am using Asp.Net Core Razor pages, my jquery is in the View. I tried both solutions, Satya and Sachin but is not working. The page is loading perfectly without this function but is not working because of the model is null.
I don't see how to use model validation Srinivasan, I am not having issues in code behind
Satya Karki4y ago
Hi, you can try this
if ($("#YourFormName").valid()) {
//checkA
                        if($("#rasA").hasClass("colorA") && checkA == "@Model.IntrebareClass.CorectA")
                        {
                            $("#rasA").css("background-color", "green")
                        }
}
To validate from Controller, you can use ModelState
if (!ModelState.IsValid) return BadRequest("Enter required fields");
Sachin Singh4y ago
test this
$(function(){
                $("#btnVer").on("click", function(){
                var cond="@Model.IntrebareClass";
                    if(cond!=' ')
                    {
                        //checkA
                        if($("#rasA").hasClass("colorA") && checkA == "@Model.IntrebareClass.CorectA")
                        {
                            $("#rasA").css("background-color", "green")
                        }
Srinivasan Ramamoorthi4y ago
Use modelstate.isvalid Check this link https://docs.microsoft.com/en-us/aspnet/core/mvc/models/validation?view=aspnetcore-6.0