如何将多个字符串变为一个？

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

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

# 使用join()方法连接多个字符串
strings = ["Hello", "World"]
result = " ".join(strings)
print(result) # Output: "Hello World"

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

// 使用StringBuilder类连接多个字符串
StringBuilder sb = new StringBuilder();
sb.append("Hello");
sb.append(" ");
sb.append("World");
String result = sb.toString();
System.out.println(result); // Output: "Hello World"