Set snap on or off by user

[Dutchstyler]

Just work with the script for 2 weeks and love it.
But is it possible to set the snap on and off? Tryed a few things but I 'm to new with this to understand.

Thouht to set a input value and read this out to edit the modifier. But that`s not working.

What I have by now:

var gridTarget = interact.snappers.grid({
// can be a pair of x and y, left and top,
// right and bottom, or width, and height
x: document.getElementById("gridsnap").value,
y: 10

});

// target elements with the "draggable" class
interact('.draggable')
.draggable({
// enable inertial throwing
inertia: false,
modifiers: [
/*
interact.modifiers.snap({
targets: [
//interact.snappers.grid({ x: 3.5, y: 3.5 })
gridTarget
],
range: Infinity,
relativePoints: [ { x: 0, y: 0 } ]
}),*/
interact.modifiers.snap({ targets: [gridTarget] }),
interact.modifiers.restrictRect({ //Blijf binnen het huidige element.
restriction: 'parent',
endOnly: false
})
],

// enable autoScroll
autoScroll: false,

listeners: {
  // call this function on every dragmove event
  move: dragMoveListener,

  // call this function on every dragend event
  end (event) {


  }
}

})