你需要使用排序器功能，并根据你的用例更新逻辑，如下所示，

Ext.application({
    name: 'YourApp',
    launch: function () {
        var Store = Ext.create('Ext.data.Store', {
            data: [
                { sampledata: 'A 1' },
                { sampledata: 'A 11' },
                { sampledata: 'A 2' },
                { sampledata: 'A 21' },
                { sampledata: 'A 3' }
            ],
            sorters: [{
                sorterFn: function(item1, item2) {
                    var pattern = /([A-Za-z]+) (\d+)/;
                    var match1 = item1.get('sampledata').match(pattern);
                    var match2 = item2.get('sampledata').match(pattern);
                    var groupComparison = match1[1].localeCompare(match2[1]);
                    if (groupComparison !== 0) {
                        return groupComparison;
                    }
                    var num1 = parseInt(match1[2], 10);
                    var num2 = parseInt(match2[2], 10);
                    return num1 - num2;
                }
            }]
        });
        Ext.create('Ext.form.ComboBox', {
            store: Store,
            displayField: 'sampledata',
            fieldLabel: 'ComboBox',
            renderTo: Ext.getBody()
        });
    }
});

字符串