I am passing a boolean value to a javascript function in my .net mvc action page.
problem is, it is outputting the value True and javascript apparently only accepts 'true' (in lower case).
I don't want to hack the variable and make it a string and convert it to lower case in my action, but it looks like I have no choice?
If you're using the ToString() method on a .NET boolean to send the value to Javascript, try replacing it with something like
(myBoolean ? "true" : "false")
so that it gets sent to Javascript as the appropriate string representation of the required bool value.
EDIT: Note the difference between:
<script type="text/javascript">
var myBoolean = <%= (myBoolean ? "true" : "false") %>;
</script>
and
<script type="text/javascript">
var myBoolean = '<%= (myBoolean ? "true" : "false") %>';
</script>
In the first example, you end up with:
var myBoolean = false;
and that's a literal Boolean false. In the second, you end up with:
var myBoolean = 'false';
and in JavaScript, 'false' is a non-empty string and consequently if evaluated in a Boolean context, it'll be true. Well, true-ish. :)
I created an extension method to use it in any boolean property of a Model.
public static class GeneralExtensions
{
public static string GetValueForJS(this bool argValue)
{
return argValue ? "true" : "false";
}
}
Now in a view I can simply use:
<script type="text/javascript">
var variable = @Model.IsFoo.GetValueForJS();
</script>
if you need to do this often, just add this to the top of the javascript (or your js library file, etc.)
var True = true; False = false;
in a simple one off case use:
var x = ('<%= boolValue %>'=='True' );
For me, this approach works (MVC4)
<script type="text/javascript">
if (@{if (Model.IsSubmitted) { @Html.Raw("true"); } else { @Html.Raw("false"); } } == true)
{
// code
}
</script>
if (@Html.Raw(Model.IsSubmitted?"true":"false"))You can use the javascript Boolean() method
if (Boolean(value)) {}
You want to use this:
(.NET 3.5) System.Web.Script.Serialization.JavaScriptSerializer.Serialize
I wrote a public js method, when i need to check a passed boolean variable from action in javaScript, just send the original value to this method to parse.
function GetBooleanValue(value) {
if (value == undefined) return false;
var parsedValue = value.toLowerCase();
if (parsedValue === "false") return false;
else if (parsedValue === "true") return true;
else return false;
}
