Question

我使用promises进行多次ajax调用如何通过设置标志返回上一个函数。我有一个保存函数，我在其中调用方法if(!x()){return;}我想从x函数中返回一些标志我使用promises进行ajax调用，因为我需要等待多个ajax请求响应并依赖于它我必须提交表格。请检查小提琴Fiddle

Answer 1

除非你熟悉Promises，否则这种事情是一场噩梦。

据我所知，你想要这样的东西：

Ext.define('MyApp.view.MyModel1FormViewController', {
    'extend': 'Ext.app.ViewController',
    'alias': 'controller.mymodel1form',
    'save': function (button, e, eOpts, processed) {
        var me = this;
        // enable/disable "submit" button based on Promise-wrapped result from refValid()
        return this.refValid().then(function(bool) {
            // success handler
            me.onSubmit(button, e, eOpts, bool);
            Ext.Msg.alert('save: success');
        }, function (e) {
            // error handler
            // me.onSubmit(button, e, eOpts, ???); true|false or maybe just leave the button in its current state?
            Ext.Msg.alert('save: errors');
            // throw e; // rethrow the error to inform save()'s caller.
        });
    },
    'refValid': function (button, e, eOpts) {
        var detailStore = this.getView().up('panel').lookupReference('list').getStore(),
            jde = this.getView().up('panel').lookupReference('headerform').lookupReference('jdeno').getValue();
        var promises = detailStore.data.items.map(function (r) { // ???
            return r.get('refno') || null;
        }).filter(function (x) {
            return !!x; // filter out any nulls
        }).map(function (customerInvoiceDebitNo) {
            return Ext.Ajax.request({
                'url': 'data1.json',
                'timeout': 120000,
                'method': 'GET',
                'params': {
                    'addressNumber': jde,
                    'documentNumber': customerInvoiceDebitNo
                },
                'customerInvoiceDebitNo': customerInvoiceDebitNo
            }).then(function (response) {
                if (Ext.decode(response.responseText).data.length === 0) {
                    return false; // null
                } else {
                    Ext.Array.remove(customerInvoiceDebitNo); // maybe not necessary?
                    return true; // not null
                }
            });
        });
        return Ext.Promise.all(promises).then(function (results) { // results is array of booleans
            // Scan the results to check whether or not all are `true`,
            // and return <boolean>.
            return results.reduce(function (prev, current) {
                return prev && current;
            }, true);
        });
    }
});

如何通过使用promises设置标志来返回上一个函数

1 个答案: