The specific difference between M-step and D method in thinkphp

The specific differences between M and D methods in thinkphp

The difference between the M method and the D method

Both the M method and the D method in thinkphp are used to instantiate a model class, and the M method is used to instantiate an underlying model class efficiently, whereas the D method is used to instantiate a user-defined model class.

Using the M method

If this is the case, consider using the M method:

1. When a simple curd operation is performed on a data table without complex business logic
2. The M method is used in conjunction with the instantiated Commonmodel class when only the individual tables have more complex business logic

The M method can even simply look at the operation of the data table corresponding to the parameter table name:

Using the D method

If this is the case, consider using the D method:

1. You need to use some of the advanced features in the thinkphp model, such as the auto-Validate function (implemented in the Create () method), the correlation model, etc.
2. Business logic is more complex and involves many tables
3. The business logic is defined in the Custom model class (under the Lib/model directory), and you want to implement these business logic in the operation

In addition, the D method does not support cross-project calls, and requires the use of:

$User = D (' User ', ' Admin ');    Instantiate the User model under the Admin project $User = D (' Admin.user ');        

Tips

When item grouping is enabled, the Model class does not necessarily correspond to the grouping of items. A model class that is common among multiple project groups and is placed uniformly in the model directory and can be instantiated directly using D (' modelname '). D (' user.userinfo ') does not mean that User must be a project group, or just a catalog of files under model, and D (' user.userinfo ') instantiates the UserInfo model class under the User directory.

Summarize

Both M and D methods can be used directly in case the model class file does not exist, but the M method is obviously more efficient, but to use the business logic inside the model class, the D method must be used.

A comparative image of the analogy is: M method just like a computer installed in the operating system, can only use some basic functions, and the D method is installed on the system, such as Office, QQ and other application software, more powerful, while the whole computer running speed also slowed.

Above is a summary of the difference between M method and D method, and the M method and D method should be selected according to the actual situation.

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