js

#replace替换
var str="Hello world! world is beautiful.";
var str_new=str.replace("world","JavaScript");
console.log(str_new);

#替换全部
var str="Apple, Banana, Apple, Orange";
const str_new=str.replace(/Apple/g,"Grape");
console.log(str_new); 

#忽略大小写
const str_new= str.replace(/hello/gi,"Hi");

#In Arrray
const arr=['apple','banana','cherry'];
console.log(arr.includes('banana'));

php

#replace
$str="Hello world! world is beautiful.";
$str_new=str_replace("world","PHP",$str);
echo $str_new; 

#忽略大小写
$str="Hello HELLO hello";
$str_new=preg_replace('/hello/i','Hi',$str);
echo $str_new;

#in_array
$arr=['apple','banana','cherry'];
in_array('banana',$arr);

java

#replace
String str="Hello world! world is beautiful.";
String str_new=str.replace("world", "Java");
System.out.println(str_new);

#in array
String[] arr={"apple", "banana", "cherry"};
List<String> list=Arrays.asList(arr); 

System.out.println(list.contains("banana"));

python

#replace
s="Hello world! world is nice."
s_new=s.replace("world", "Python")
print(new_s)

#in array
arr=['apple', 'banana', 'cherry']
print('banana' in arr)