When you need to set the value of a Multiple Choice field from some other field's "On Change Click", this syntax works.

Multiple Choice Field Name: EnteringGrade2

Syntax: document.getElementById(form.fields.EnteringGrade2.id).selectedIndex = 0;

This syntax avoids using the actual field ID

The value of 0 is the default entry = "Select"

If the Button ID is FillDirectInput,

Use the following syntax to get the ID and insert into a JQuery click command

$('#'+form.fields.FillDirectInput.id).click();

A way to get the form field values from an action form

${{form.fields.BodyType.value}}

form.fields.CarsName.value
form.fields.cbYear.selected.text

In Javascript, refer to another field like the following example for the field named, 

EndDate

$scope.form.fields.EndDate.value=(in30.getMonth() + 1) + '/' + in30.getDate() + '/' + in30.getFullYear();

Or, to use the ID of another field,

$('#'+form.fields.FillDirectInput.id).click();

Hello Mark,
 

You can either use the server request action and simply call the API using that or, depending on your DNNApi version there is a second action called Execute Api Method which skips the HTTP protocol and executes the method directly.

Kind regards,
Cristian P.

This js will put a query string parameter into the URL

dnnsf.updateQueryStringParam('label',[value]);

Where I got this: https://blog.dnnsharp.com/1001/64-how-to-build-a-file-manager

Remove all params from the Querystring

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