如何使用字符串连接？

String str1 = "Hello";
String str2 = "World";
String result = str1 + " " + str2;
System.out.println(result); // 输出：Hello World

str1 = "Hello"
str2 = "World"
result = str1 + " " + str2
print(result)  # 输出：Hello World

# 使用join()方法连接字符串
str_list = ["Hello", "World"]
result = " ".join(str_list)
print(result)  # 输出：Hello World

let str1 = "Hello";
let str2 = "World";
let result = str1 + " " + str2;
console.log(result); // 输出：Hello World

// 使用字符串模板连接字符串
let str1 = "Hello";
let str2 = "World";
let result = `${str1} ${str2}`;
console.log(result); // 输出：Hello World

string str1 = "Hello";
string str2 = "World";
string result = str1 + " " + str2;
Console.WriteLine(result); // 输出：Hello World

// 使用字符串插值连接字符串
string str1 = "Hello";
string str2 = "World";
string result = $"{str1} {str2}";
Console.WriteLine(result); // 输出：Hello World