这是我在下面尝试的但是firstName绑定将函数作为字符串返回而不是执行它(http://jsfiddle.net/W37Yh).

var Homeviewmodel = function(config,$,undefined) {

    if (!this instanceof Homeviewmodel) {
        return new Homeviewmodel(config,undefined);
    }

    this.firstName = ko.observable(config.firstName);
    this.lastName = ko.observable(config.lastName);
};

Homeviewmodel.prototype.fullName = function() {
    return ko.computed(function() {
        return this.firstName() + " " + this.lastName();
    },this);
};

var model = new Homeviewmodel({
    firstName: "John",lastName: "Smith"
},jQuery);

ko.applyBindings(model);​