Model类，集中整个应用的数据和业务逻辑——
/**
* Generates a user friendly attribute label based on the give attribute name.
* 生成一个对用户友好的属性标签，将属性名中的下划线、破折号、点替换为空格，并且每个单词的首字母大写
* This is done by replacing underscores, dashes and dots with blanks and
* changing the first letter of each word to upper case.
* For example, 'department_name' or 'DepartmentName' will generate 'Department Name'.
* @param string $name the column name
* @return string the attribute label
*/
public function generateAttributeLabel($name)
{
//调用Inflector::camel2words()方法生成用户友好的属性标签，属于辅助方法
return Inflector::camel2words($name, true);
}
/**
* Returns attribute values.
* 返回属性值，如不指定属性名，则返回所有[[attributes()]]中的属性的属性值，第二个参数用来指定不返回的属性值
* @param array $names list of attributes whose value needs to be returned.
* Defaults to null, meaning all attributes listed in [[attributes()]] will be returned.
* If it is an array, only the attributes in the array will be returned.
* @param array $except list of attributes whose value should NOT be returned.
* @return array attribute values (name => value).
*/
public function getAttributes($names = null, $except = [])
{
$values = [];
if ($names === null) {
//属性名为空，则返回所有[[attributes()]]中的属性的属性值
$names = $this->attributes();
}
foreach ($names as $name) {
//指定属性名（数组格式），遍历返回属性值
$values[$name] = $this->$name;
}
foreach ($except as $name) {
//如果指定排除的属性值，则注销该属性值
unset($values[$name]);
}
return $values;
}
/**
* Sets the attribute values in a massive way.
* 批量设置属性值
* @param array $values attribute values (name => value) to be assigned to the model.
* @param boolean $safeOnly whether the assignments should only be done to the safe attributes.
* A safe attribute is one that is associated with a validation rule in the current [[scenario]].
* @see safeAttributes()
* @see attributes()
*/
public function setAttributes($values, $safeOnly = true)
{
// 判断传入的属性值是否为数组
if (is_array($values)) {
// array_flip — 交换数组中的键和值
// 将属性放到了 key 上
// 默认取 safeAttributes 中的属性
$attributes = array_flip($safeOnly ? $this->safeAttributes() : $this->attributes());
foreach ($values as $name => $value) {
if (isset($attributes[$name])) {
// 如果存在该属性，就直接赋值
$this->$name = $value;
} elseif ($safeOnly) {
// 如果不存在，而且是 safeOnly 的话，就触发一下 onUnsafeAttribute 方法
$this->onUnsafeAttribute($name, $value);
}
}
}
}
/**
* This method is invoked when an unsafe attribute is being massively assigned.
* 该方法在一个unsafe属性被批量赋值时被调用，如果是调试状态，就写入log 记录下没有成功设置的不安全的属性
* The default implementation will log a warning message if YII_DEBUG is on.
* It does nothing otherwise.
* @param string $name the unsafe attribute name
* @param mixed $value the attribute value
*/
public function onUnsafeAttribute($name, $value)
{
if (YII_DEBUG) {
// 如果是调试状态，就写入log 记录下没有成功设置的不安全的属性
Yii::trace("Failed to set unsafe attribute '$name' in '" . get_class($this) . "'.", __METHOD__);
}
}
/**
* Returns the scenario that this model is used in.
* 获取当前模型的使用场景
*
* Scenario affects how validation is performed and which attributes can
* be massively assigned.
* 场景可以影响批量赋值属性的验证
*
* @return string the scenario that this model is in. Defaults to [[SCENARIO_DEFAULT]].
*/
public function getScenario()
{
// 获取当前的场景
return $this->_scenario;
}
/**
* Sets the scenario for the model.
* Note that this method does not check if the scenario exists or not.
* The method [[validate()]] will perform this check.
* @param string $value the scenario that this model is in.
*/
public function setScenario($value)
{
// 设置当前的场景
$this->_scenario = $value;
}
/**
* Returns the attribute names that are safe to be massively assigned in the current scenario.
* 批量返回当前场景中安全的属性名
* @return string[] safe attribute names
*/
public function safeAttributes()
{
// 获取当前的场景
$scenario = $this->getScenario();
// 获取所有场景及其属性
$scenarios = $this->scenarios();
if (!isset($scenarios[$scenario])) {
// 场景不存在，就返回空
return [];
}
$attributes = [];
foreach ($scenarios[$scenario] as $attribute) {
// 将开头不是！的属性才会放入到 safeAttributes 中, 即以！开头的属性不会被放到 safeAttributes 中
if ($attribute[0] !== '!') {
$attributes[] = $attribute;
}
}
return $attributes;
}
/**
* Returns the attribute names that are subject to validation in the current scenario.
* 返回在默认场景中验证的属性名
* @return string[] safe attribute names
*/
public function activeAttributes()
{
// 获取当前的场景
$scenario = $this->getScenario();
// 获取所有场景及其属性
$scenarios = $this->scenarios();
if (!isset($scenarios[$scenario])) {
return [];
}
$attributes = $scenarios[$scenario];
foreach ($attributes as $i => $attribute) {
// 如果属性名以！开头，就把！截取掉
// ！开头的属性来自rules，加！能够使规则（即 validator）生效，但却能够不出现在 safeAttributes 中
if ($attribute[0] === '!') {
$attributes[$i] = substr($attribute, 1);
}
}
return $attributes;
}
/**
* Populates the model with input data.
* 用输入的数据填充模型
* This method provides a convenient shortcut for:
* 该方法提供了一个方便快捷的方式：
*
* ```php
* if (isset($_POST['FormName'])) {
* $model->attributes = $_POST['FormName'];
* if ($model->save()) {
* // handle success
* }
* }
* ```
*
* which, with `load()` can be written as:
*
* ```php
* if ($model->load($_POST) && $model->save()) {
* // handle success
* }
* ```
*
* `load()` gets the `'FormName'` from the model's [[formName()]] method (which you may override), unless the
* `$formName` parameter is given. If the form name is empty, `load()` populates the model with the whole of `$data`,
* instead of `$data['FormName']`.
*
* Note, that the data being populated is subject to the safety check by [[setAttributes()]].
*
* @param array $data the data array to load, typically `$_POST` or `$_GET`.
* @param string $formName the form name to use to load the data into the model.
* If not set, [[formName()]] is used.
* @return boolean whether `load()` found the expected form in `$data`.
*/
public function load($data, $formName = null)
{
// 如果存在 yii 的 form，就使用该 form，否则就取所在类的名称（不含 namespace）
$scope = $formName === null ? $this->formName() : $formName;
if ($scope === '' && !empty($data)) {
// 如果 $scope 为空字符串，且 $data不为空，就设置属性，即创建
$this->setAttributes($data);
return true;
} elseif (isset($data[$scope])) {
// 否则，必须存在 $data[$scope]，使用 $data[$scope] 去设置属性
$this->setAttributes($data[$scope]);
return true;
} else {
return false;
}
}
/**
* Populates a set of models with the data from end user.
* 加载数据到所在的 model 的集合中
* This method is mainly used to collect tabular data input.
* 此方法主要用于收集表格数据输入
* The data to be loaded for each model is `$data[formName][index]`, where `formName`
* refers to the value of [[formName()]], and `index` the index of the model in the `$models` array.
* If [[formName()]] is empty, `$data[index]` will be used to populate each model.
* The data being populated to each model is subject to the safety check by [[setAttributes()]].
* @param array $models the models to be populated. Note that all models should have the same class.
* @param array $data the data array. This is usually `$_POST` or `$_GET`, but can also be any valid array
* supplied by end user.
* @param string $formName the form name to be used for loading the data into the models.
* If not set, it will use the [[formName()]] value of the first model in `$models`.
* This parameter is available since version 2.0.1.
* @return boolean whether at least one of the models is successfully populated.
*/
public static function loadMultiple($models, $data, $formName = null)
{
if ($formName === null) {
//表名为空
// reset — 将数组的内部指针指向第一个单元
$first = reset($models);
if ($first === false) {
// $models不存在就返回 false
return false;
}
// 取得所在类的名称（不含 namespace）
$formName = $first->formName();
}
$success = false;
// 遍历 $models，一个个加载数据
foreach ($models as $i => $model) {
if ($formName == '') {
if (!empty($data[$i])) {
// 数据不为空，就 load 到相应的 model 中
$model->load($data[$i], '');
$success = true;
}
} elseif (!empty($data[$formName][$i])) {
// 存在 $formName，且数据不为空，就 load 到相应的 model 中
$model->load($data[$formName][$i], '');
$success = true;
}
}
return $success;
}
/**
* Validates multiple models.
* 验证多个模型
* This method will validate every model. The models being validated may
* be of the same or different types.
* @param array $models the models to be validated
* @param array $attributeNames list of attribute names that should be validated.
* If this parameter is empty, it means any attribute listed in the applicable
* validation rules should be validated.
* @return boolean whether all models are valid. False will be returned if one
* or multiple models have validation error.
*/
public static function validateMultiple($models, $attributeNames = null)
{
$valid = true;
/* @var $model Model */
foreach ($models as $model) {
//遍历$models 调用validate（）方法
$valid = $model->validate($attributeNames) && $valid;
}
return $valid;
}
/**
* Returns the list of fields that should be returned by default by [[toArray()]] when no specific fields are specified.
* 以数组形式返回一个字段名或字段定义
* A field is a named element in the returned array by [[toArray()]].
*
* This method should return an array of field names or field definitions.
* 此方法应该返回一个字段名或字段定义的数组
* If the former, the field name will be treated as an object property name whose value will be used
* as the field value. If the latter, the array key should be the field name while the array value should be
* 如果前者，该字段名将被视为一个对象属性名，其值将用作该字段值。
* the corresponding field definition which can be either an object property name or a PHP callable
* 如果是后者，数组的键应该是字段名称，数组的值应相应的字段定义可以是一个对象的属性名称或PHP回调函数
* returning the corresponding field value. The signature of the callable should be:
*
* ```php
* function ($model, $field) {
* // return field value
* }
* ```
*
* For example, the following code declares four fields:
*
* - `email`: the field name is the same as the property name `email`;
* - `firstName` and `lastName`: the field names are `firstName` and `lastName`, and their
* values are obtained from the `first_name` and `last_name` properties;
* - `fullName`: the field name is `fullName`. Its value is obtained by concatenating `first_name`
* and `last_name`.
*
* ```php
* return [
* 'email',
* 'firstName' => 'first_name',
* 'lastName' => 'last_name',
* 'fullName' => function ($model) {
* return $model->first_name . ' ' . $model->last_name;
* },
* ];
* ```
*
* In this method, you may also want to return different lists of fields based on some context
* information. For example, depending on [[scenario]] or the privilege of the current application user,
* you may return different sets of visible fields or filter out some fields.
* 在这个方法中，可能还希望在根据条件返回不同的字段列表，例如，根据[[scenario]]或者当前应用程序用户的权限
* 设置不同的可见字段或者过滤某些字段
*
* The default implementation of this method returns [[attributes()]] indexed by the same attribute names.
* 默认返回[[attributes()]]中的属性名为索引的所有字段
* @return array the list of field names or field definitions.
* @see toArray()
*/
public function fields()
{
$fields = $this->attributes();
// array_combine — 创建一个数组，用一个数组的值作为其键名，另一个数组的值作为其值
return array_combine($fields, $fields);
}
/**
* Returns an iterator for traversing the attributes in the model.
* 返回模型中一个遍历属性的迭代器
* This method is required by the interface [[\IteratorAggregate]].
* @return ArrayIterator an iterator for traversing the items in the list.
*/
public function getIterator()
{
// 获取该 model 的所有属性
$attributes = $this->getAttributes();
// ArrayIterator 这个迭代器允许在遍历数组和对象时删除和更新值与键
// 当你想多次遍历相同数组时你需要实例化 ArrayObject，然后让这个实例创建一个 ArrayIteratror 实例, 然后使用 foreach 或者 手动调用 getIterator() 方法
return new ArrayIterator($attributes);
}
/**
* Returns whether there is an element at the specified offset.
* This method is required by the SPL interface [[\ArrayAccess]].
* It is implicitly called when you use something like `isset($model[$offset])`.
* @param mixed $offset the offset to check on
* @return boolean
*/
public function offsetExists($offset)
{
// 将 isset($model[$offset]) 重写为 isset($model->$offset)
return $this->$offset !== null;
}
/**
* Returns the element at the specified offset.
* 获取指定下标的元素
* This method is required by the SPL interface [[\ArrayAccess]].
* 该方法将[[\ArrayAccess]]接口中的数组访问模式改写为对象访问模式
* It is implicitly called when you use something like `$value = $model[$offset];`.
* @param mixed $offset the offset to retrieve element.
* @return mixed the element at the offset, null if no element is found at the offset
*/
public function offsetGet($offset)
{
// 将获取 $model[$offset] 重写为 $model->$offset
return $this->$offset;
}
/**
* Sets the element at the specified offset.
* 设置指定下标的元素
* This method is required by the SPL interface [[\ArrayAccess]].
* 该方法将[[\ArrayAccess]]接口中的数组访问模式改写为对象访问模式
* It is implicitly called when you use something like `$model[$offset] = $item;`.
* @param integer $offset the offset to set element
* @param mixed $item the element value
*/
public function offsetSet($offset, $item)
{
// 将 $model[$offset] = $item 重写为 $model->$offset = $item
$this->$offset = $item;
}
/**
* Sets the element value at the specified offset to null.
* 删除指定下标的元素
* This method is required by the SPL interface [[\ArrayAccess]].
* 该方法将[[\ArrayAccess]]接口中的数组访问模式改写为对象访问模式
* It is implicitly called when you use something like `unset($model[$offset])`.
* @param mixed $offset the offset to unset element
*/
public function offsetUnset($offset)
{
// 将 unset($model[$offset]) 重写为 $model->$offset = null
$this->$offset = null;
}