How to bind a toggle button using knock out

I have written the below code to see the working of Toggle Button. But it seems the data bind is not working.

Below is the HTML code

  <div>
        <label class="switch">
            <input type="checkbox" id="toggle123" data-bind="click:isToggleTrueOrFalse" />
            <span class="slider round"></span>
        </label>
    </div>

Below is the Style

<style>

         .switch {
            position: relative;
            display: inline-block;
            width: 60px;
            height: 34px;
        }

        .switch input {
            opacity: 0;
            width: 0;
            height: 0;
        }

        .slider {
            position: absolute;
            cursor: pointer;
            top: 0;
            left: 0;
            right: 0;
            bottom: 0;
            background-color: #ccc;
            -webkit-transition: .4s;
            transition: .4s;
        }

            .slider:before {
                position: absolute;
                content: "";
                height: 26px;
                width: 26px;
                left: 4px;
                bottom: 4px;
                background-color: white;
                -webkit-transition: .4s;
                transition: .4s;
            }

        input:checked + .slider {
            background-color: #2196F3;
        }

        input:focus + .slider {
            box-shadow: 0 0 1px #2196F3;
        }

        input:checked + .slider:before {
            -webkit-transform: translateX(26px);
            -ms-transform: translateX(26px);
            transform: translateX(26px);
        }

        /* Rounded sliders */
        .slider.round {
            border-radius: 34px;
        }

            .slider.round:before {
                border-radius: 50%;
            }


    </style>

Below is the script

<script>
    self.isToggleTrueOrFalse = ko.computed(function () {
        if (document.getElementById('toggle123').checked) {
            // return true;
            console.log("true");
        }
        else {
            console.log("false");
        }
    }, self);
</script>

My requirement is when clicking on the toggle button I have to get the true or false in the console. Currently only false is coming in console.

Also I have tried using

<script>
        this.toggleAssociation1=function () {
            var checkBox = document.getElementById("toggle123");
            if (checkBox.checked == true)
            {
                return true;
            }
            else
            {
                return false;
            }
        }
    </script>

and

<input type="checkbox" id="toggle123" data-bind="click:toggleAssociation1" />

but it also did not work.

Will click event work for this. Or shall we have to use any other event.

Can some one help me on this.