如何在sencha touch / ext js模型中编写验证

Question

I have a model like this

Ext.define('app.model.TeamEmpAssignment', {
            extend : 'Ext.data.Model',
            config : {
                idProperty : 'teamEmpId',
                fields : [{
                        name : 'teamEmpId',
                        type : 'int'
                    }, {
                        name : 'actName'
                    }, {
                        name : 'beginDateTime'
                    }, {
                        name : 'endDateTime'
                    },

                ],

                validations : [{
                        field : 'beginDateTime',
                        type : 'presence',
                        message : 'Effective Begin Date Time required'
                    }, {
                        field : 'endDateTime',
                        type : 'presence',
                        message : 'Effective End Date Time required'
                    },
                ],

            }

        });

I have to write a validation to compare that endDateTime > startDateTime

I am trying sencha touch 2.3.1

Answer 1

I know this is an old question, but I ran into it while dealing with the same problem and wanted to share my approach.

I created a method in the model, which does the custom validation, something like:

Ext.define('app.model.TeamEmpAssignment', {
    extend : 'Ext.data.Model',
    config : {
        // config here
    },

    checkDates: function (errors) {
        // assuming the dates are timestamps
        if (this.get('beginDateTime') > this.get('endDateTime')) {
            errors.add(Ext.create('Ext.data.Error', {
                field  : 'beginDateTime',
                message: 'Begin date can\'t be after end date'
            }));
        }
    }

});

You will notice that checkDates has one argument - errors. This argument is actually the Ext.data.Errors object return by the validate method of the model. So we can do something like:

var record = Ext.create('Ext.data.Errors');
// set some values here
var errors = record.validate();
record.checkDates(errors);

console.log(errors.isValid());

We can use isValid, because all it does is check whether the Ext.data.Errors collection has items.

I am currently using it like this, however it will be quite easy to override the validate method, so you don't have to call the custom validation externaly.

Ext.define('app.model.TeamEmpAssignment', {
    extend : 'Ext.data.Model',
    config : {
        // config here
    },

    checkDates: function (errors) {
        // assuming the dates are timestamps
        if (this.get('beginDateTime') > this.get('endDateTime')) {
            errors.add(Ext.create('Ext.data.Error', {
                field  : 'beginDateTime',
                message: 'Begin date can\'t be after end date'
            }));
        }
    },

    validate: function () {
        var errors = this.callParent(arguments);

        this.checkDates(errors);

        return errors;
    }

});

Answer 2

The validation types come from the Ext.data.validations singleton. You can add your own validators here, however the method does not supply the all the fields in the model (which it sounds like you will need). We would advise moving your validators to a different spot (outside the model), maybe on the related form component (after a load or before a save).