What are arrays and two-dimensional arrays in php?

What are arrays and two-dimensional arrays in php? I understand now that an eheo is so sad! I thought I still couldn’t tell the difference between arrays and two-digit arrays! I beg the teacher to give me some pointers. Thank you.

Administrator(长风大侠) 2020-05-29 15:13:00 0  2  1100

Merge associative arrays with shared column values

I want to merge two arrays based on common column values. Here are my 2 arrays: $array1=[["total_process_per_category"=>"6","category_id"=>"1"],["total_process_per_category"=>"2","ca

P粉966979765 2023-11-09 08:47:41 0  2  546

Facade is similar to class inheritance, right?

Facade is similar to class inheritance, right?

︿ 2019-03-02 17:04:13 0  3  1193

javascript - Category editor retains previous category name

Now there is such a demand. Due to the unreasonable design of the previous classification, it is now necessary to edit the classification and the previous classification name (called the old classification name) is not in the editing classification drop-down list. However, when querying, the old cla...

黄舟 2017-06-30 09:52:43 0  2  990

javascript - Add a pseudo-class to a certain class. This class has a click event. Now when I click on the pseudo-class, the click event is also triggered.

Add a pseudo-class to a certain class. This class has a click event. Now when I click on the pseudo-class, the click event is also triggered. How can I prevent the click event from being triggered by clicking on the pseudo-class?

欧阳克 2017-07-05 10:44:13 0  2  984

Convert base class instance to derived class without typecasting in typescript

I extended a new class from the base class and added some properties. How to create an instance of a derived class using a given base class (including attached properties)? This code works but casts the class type and is not type safe. How can I do this without type casting? //Baseclassisimportedfro...

P粉451614834 2024-02-25 19:48:09 0  2  344

Is the class identifier the key of the array?

Is the class identifier the key of the array?

齐天大宅 2023-10-04 00:37:56 1  0  673

Copy the values ​​of an array

When copying one array to another in JavaScript: vararr1=['a','b','c'];vararr2=arr1;arr2.push('d');//Now, arr1=[ 'a','b','c','d'] I realized that arr2 was referencing the same array as arr1, not a new, separate array. How do I copy an array to get two separate arrays?

P粉002546490 2023-08-20 12:42:44 0  2  470

Merge two arrays in the same row JQUERY

I have a problem that I can't merge two arrays in the same row, I have two arrays now and then I want to merge them because they have the same length Here are my two arrays and it looks like what I want by combining output like this, but this is what I tried constar1=$('input[class=namecheckbox]').m...

P粉610028841 2024-04-03 14:41:39 0  1  340

javascript - array merging problem

This is the two arrays before merging. This is the array after merging. How to write this foreach?

迷茫 2017-06-28 09:23:28 0  2  891

Problem assigning base class pointer to derived class

Assign the derived class address to the base class pointer, that is, the base class pointer refers to the derived class object, which is what we usually call polymorphism. But when it is the other way around, it must be forced type conversion before it can be compiled. Here is the direct code: {code...

曾经蜡笔没有小新 2017-06-05 11:11:46 0  3  1123

If PHP uses multi-dimensional arrays, will the efficiency be very low?

When using PHP to do projects, you need to use a data structure to store data, but in PHP, it seems that it can only be stored using arrays. The configuration files of PHP's Laravel and other frameworks all use multi-dimensional arrays, such as: {code...} I think the efficiency of multi-dimensional ...

PHP中文网 2017-06-15 09:22:11 0  7  822

Will calling a static method directly using the class name in PHP trigger the constructor of the class or parent class?

As the title says, PHP calls static methods directly using the class name. Two questions: 1. Will the constructor of the current class be called? 2 Will the constructor of the parent class of the current class be called?

淡淡烟草味 2017-07-07 10:34:10 0  3  1339

Is there a class tree?

Is there a class tree?

二哥 2021-02-21 19:08:28 0  1  1155

How smarty template traverses arrays

{foreach from=$goods from is equivalent to the name of the array to be looped key=key key is equivalent to key item=goods item is equivalent to value }{$key}: {$goods}<br>{/foreach}

不晓得 2018-09-23 20:42:31 0  1  833

javascript - JS inheritance, how to avoid the situation where the object type attribute of the parent class prototype will be affected by the subclass;

Parent is the parent class, and child inherits parent. When the sex value of the child instance is modified, it will cause the sex of the parent and other subclass instances to change; whether this type of object type attributes can only be placed in the constructor, or whether it is agreed upon All...

过去多啦不再A梦 2017-06-30 09:59:00 0  4  841

Why do I get a variable type error when adding: array

Why do I get a variable type error when adding: array

海绵宝宝 2018-08-08 13:38:31 0  2  1748