Array and string processing, common status codes, differences between PHP and JS (JS)

Personally collated from 2019 year , Although it looks untidy , But true and reliable , Self use

Catalog

splice

pop() Method

String segmentation

Remove the characters  

math

Status code

Php  js The difference between

 

---

splice

When a negative number is used as an argument, it means counting from the end of the array . When the second optional parameter is omitted , Means to copy to the end of the array . So use on arrays slice(-1) You can get the last element of the array .(-1 Last element ,-2 The second last element ) 

var args = [1, 2, 3];

var lastElement = args.slice(-1);//3

 Delete current element  arr.slice(i,1)

 

pop() Method

pop() Method , Delete the last element of the array and return it Using this method, we can get the last one of the array , Empathy shift() You can get the first one in the array (shift() Delete the first element of the array and return that element )

var arr=[1,2,3];

arr.pop()  // Delete the last element of the array and return the deleted element   3

String segmentation

this.local_get=[12,22,33]   

var arrayA = this.local_get.split(",");

Remove the characters  

 

math

 

 

 

Status code

1**： Request received , To continue processing

2**： Operation successfully received , analysis , Accept

3**： Further analysis is required to complete this request

4**： The request contains a bad syntax or cannot be completed

5**： The server failed to execute a fully valid request

100： Customer must continue to request

101： The client requires the server to convert according to the request HTTP Protocol version

200： Successful trade

201： Mention that you know the new document URL

202： To accept and deal with 、 But the processing is not complete

400： Wrong request , Such as grammatical errors

401： Request authorization failed

402： Keep valid ChargeTo Head response

403： The request does not allow

404: No documents found 、 Query or URL

Php  js The difference between

	js	php
notes	//..  /* */	//.. /* */
Defining variables	var sum=2;	$sum=2;
Print	console.log(sum);	echo $sum:
function	Direct shortcut key open	Put the code in the server , Then in the matching browser 127.0.0.1 find
Define an array , And print	var arr=[1,2,'a']; console.log(arr);	$arr=array(1,3,'5'); print_r($arr); echo $arr[1];
Line break	<br>	echo '<br>';
object	var person={ 'name':'tom', 'age':13, 'sex':' male ' };	$person=array('name'=>'tom', 'age'=>13, 'sex'=>' male ');
if	var age=18; if(age>=18){ console.log( ' adults '); }else{ console.log(' minors '); }	$age=18; if($age>=18){ echo ' adults '; }else{ echo ' minors '; }
Three orders	var age=12; var res=(age>=18)? ' adults ':' A minor '; console.log(res);	$age=12; $res=($age>=18)? ' adults ':' A minor '; echo $res;
switch	var age=18; switch(age){ case 0: console.log(' A minor '); break; case 18: console.log( ' adults '); break; default: console.log(0); }	$age=18; switch($age){ case 0: echo ' A minor '; break; case 18: echo ' adults '; break; default: echo '0'; }
for	A little	$arr=array(1,2,4); for($i=0;$i<count($arr);$i++){ echo $arr[$i]; echo '<br>'; }
while	A little	$arr=array(1,2,4); $index=0; while($index<count($arr)){ echo $arr[$index]; echo '<br>'; $index++; }