Supporting ReplaceWith for AjaxOption.InsertionMode: It is occasionally convenient to be able to update content including the target container. This avoids a separate container to wrap the partial view statement.

InsertionModeReplaceWithExample.cshtml

@{
    var ajaxOptions = new AjaxOptions { UpdateTargetId = "form" };
    var htmlAttributes = new { id = "form", data_ajax_mode = "replacewith" };
}

@using (Ajax.BeginForm("Index", null, ajaxOptions, htmlAttributes))
{
    
}

jquery.unobtrusive-ajax.js

function asyncOnSuccess(element, data, contentType) {
    var mode;

    if (contentType.indexOf("application/x-javascript") !== -1) {
        return;
    }

    mode = (element.getAttribute("data-ajax-mode") || "").toUpperCase();
    $(element.getAttribute("data-ajax-update")).each(function (i, update) {
        var top;

        switch (mode) {
        case "BEFORE":
            top = update.firstChild;
            $("<div />").html(data).contents().each(function () {
                update.insertBefore(this, top);
            });
            break;
        case "AFTER":
            $("<div />").html(data).contents().each(function () {
                update.appendChild(this);
            });
            break;
        case "REPLACEWITH":
            $(update).replaceWith(data);
            break;
        default:
            $(update).html(data);
            break;
        }
    });
}

jquery.unobtrusive-ajax.min.js

function h(c,b,e){var d;if(e.indexOf("application/x-javascript")!==-1)return;d=(c.getAttribute("data-ajax-mode")||"").toUpperCase();a(c.getAttribute("data-ajax-update")).each(function(f,c){var e;switch(d){case"BEFORE":e=c.firstChild;a("<div />").html(b).contents().each(function(){c.insertBefore(this,e)});break;case"AFTER":a("<div />").html(b).contents().each(function(){c.appendChild(this)});break;case"REPLACEWITH":a(c).replaceWith(b);break;default:a(c).html(b)}})}