Access a Model property in a javascript file?

Question

Is it possible to access a Model property in an external Javascript file?

e.g. In \"somescript.js\" file

var currency = \'@Model.Currency\';
alert(cu         


        

Answer 1

What i did was create a js object using the Method Invocation pattern, then you can call it from the external js file. As js uses global variables, i encapsulate it to ensure no conflicts from other js libraries. Example: In the view

 @section scripts{
        <script>
            var thisPage = {
                variableOne: '@Model.One',
                someAjaxUrl: function () { return '@Url.Action("ActionName", "ControllerName")'; }            
            };
        </script>
        @Scripts.Render("~/Scripts/PathToExternalScriptFile.js")   
    }

Now inside of the external page you can then get the data with a protected scope to ensure that it does not conflict with other global variables in js.

  console.log('VariableOne = ' + thisPage.variableOne);
  console.log('Some URL = ' + thisPage.someAjaxUrl());

Also you can wrap it inside of a Module in the external file to even make it more clash proof. Example:

$(function () {
    MyHelperModule.init(thisPage || {});
});

var MyHelperModule = (function () {
    var _helperName = 'MyHelperModule';

    // default values
    var _settings = { debug: false, timeout:10000, intervalRate:60000};    

    //initialize the module
    var _init = function (settings) {

        // combine/replace with (thisPage/settings) passed in
        _settings = $.extend(_settings, settings);

        // will only display if thisPage has a debug var set to true            
        _write('*** DEBUGGER ENABLED ***');             

        // do some setup stuff              

        // Example to set up interval
        setInterval(
            function () { _someCheck(); }
            , _settings.intervalRate
        );
        return this; // allow for chaining of calls to helper  
    };

    // sends info to console for module
    var _write = function (text, always) {
        if (always !== undefined && always === true || _settings.debug === true) {
            console.log(moment(new Date()).format() + ' ~ ' + _helperName + ': ' + text);
        }
    };

    // makes the request 
    var _someCheck = function () { 
        // if needed values are in settings
        if (typeof _settings.someAjaxUrl === 'function' 
            && _settings.variableOne !== undefined) { 
            $.ajax({
                dataType: 'json'
                , url: _settings.someAjaxUrl()
                , data: {
                    varOne: _settings.variableOne                    
                }
                , timeout: _settings.timeout
            }).done(function (data) {
                // do stuff
                _write('Done');
            }).fail(function (jqxhr, textStatus, error) {                
                _write('Fail: [' + jqxhr.status + ']', true);
            }).always(function () {
                _write('Always');
            });             
        } else {// if any of the page settings don't exist
            _write('The module settings do not hold all required variables....', true);            
        }
    };

    // Public calls
    return {
        init: _init
    }; 

  })();

Answer 2

I had the same problem and I did this:

View.

`var model = @Html.Raw(Json.Encode(Model.myModel));
 myFunction(model);`

External js.

`function myFunction(model){
   //do stuff
 }`

Answer 3

I tackled this problem using data attributes, along with jQuery. It makes for very readable code, and without the need of partial views or running static javascript through a ViewEngine. The JavaScript file is entirely static and will be cached normally.

Index.cshtml:

@model Namespace.ViewModels.HomeIndexViewModel
<h2>
    Index
</h2>

@section scripts
{
    <script id="Index.js" src="~/Path/To/Index.js"
        data-action-url="@Url.Action("GridData")"
        data-relative-url="@Url.Content("~/Content/Images/background.png")"
        data-sort-by="@Model.SortBy
        data-sort-order="@Model.SortOrder
        data-page="@ViewData["Page"]"
        data-rows="@ViewData["Rows"]"></script>
}

Index.js:

jQuery(document).ready(function ($) {
    // import all the variables from the model
    var $vars = $('#Index\\.js').data();

    alert($vars.page);
    alert($vars.actionUrl); // Note: hyphenated names become camelCased
});

_Layout.cshtml (optional, but good habit):

<body>
    <!-- html content here. scripts go to bottom of body -->

    @Scripts.Render("~/bundles/js")
    @RenderSection("scripts", required: false)
</body>

Answer 4

What you could do is passing the razor tags in as a variable.

In razor File>

var currency = '@Model.Currency';
doAlert(currency);

in JS file >

function doAlert(curr){
   alert(curr);
}

Answer 5

Try JavaScriptModel ( http://jsm.codeplex.com ):

Just add the following code to your controller action:

this.AddJavaScriptVariable("Currency", Currency);

Now you can access the variable "Currency" in JavaScript.

If this variable should be available on the hole site, put it in a filter. An example how to use JavaScriptModel from a filter can be found in the documentation.

Answer 6

There is no way to implement MVC / Razor code in JS files.

You should set variable data in your HTML (in the .cshtml files), and this is conceptually OK and does not violate separation of concerns (Server-generated HTML vs. client script code) because if you think about it, these variable values are a server concern.

Take a look at this (partial but nice) workaround: Using Inline C# inside Javascript File in MVC Framework