select2 initSelection不起作用

Question

$('.select2.base-product').select2({
    minimumInputLength: 1,
    ajax: {
        url: "@Url.Action("GetBaseProducts", "Promotion")",
        dataType: 'json',
        quietMillis: 250,
        data: function(term, page) {
            return {
                searchTerm: term, // search term,
                pageSize: 15,
                pageNum: page
            };
        },
        results: function(data, page) { // parse the results into the format expected by Select2.
            return { results: data.items };
        },
        cache: true
    },
    initSelection: function(element, callback) {
        var id = $(element).val();
        var formatId = $(element).attr('data-formatid');
            if(id.length > 0) {
                $.ajax('@Url.Action("GetBaseCategoryById", "Promotion")', {
                    dataType: 'json',
                    data: {
                        id: id, formatId: formatId
                    }
                }).done(function (data) {
                    console.log(data.items);
                    callback(data.items);
                });
            }
    },
    escapeMarkup: function(markup) { return markup; } // let our custom formatter work
});

您好，初始化select2输入时遇到了很大问题。我的动作GetBaseCategoryById返回一个对象，例如

[Object]
0: Object
id: "33:2613"
text: "Naklejki: Okrągła"
__proto__: Object
length: 1
__proto__: Array[0]

对我来说这样的结果对于select2来说是正确的，但是输入是空的。有谁可以帮我这个？