下面代码的运行结果是（ ）。var str= "hello world" ;var str1=str.toUpperCase();var str2=str.toLowerCase() ;alert (str1) ;alert (str2) ;
A: "HELLO WORLD","HELLO WORLD"
B: "HELLO WORLD","hello world"
C: "hello worl","HELLO WORLD"
D: "hello world","hello world"
A: "HELLO WORLD","HELLO WORLD"
B: "HELLO WORLD","hello world"
C: "hello worl","HELLO WORLD"
D: "hello world","hello world"
举一反三
- 11字符串测试1：下列字符串定义正确的是： A: String str="Hello World!"; B: Str str="Hello World!"; C: var str="Hello World!"; D: var str='Hello World!';
- 已知$str = " Hello World! ";下列说法正确的是： A: trim($str)结果是" Hello World!"; B: ltrim($str)结果是"Hello World! "; C: trim($str)结果是" Hello World!"; D: trim($str)结果是"Hello World!";
- 如何将字符串“Hello World”写入a.txt文件内？FILE *file; file = fopen("a.txt","w"); A: char str = "Hello World"; fputs(&str,file); B: char str = "Hello World"; fputc(&str,file); C: char str = "Hello World"; fput(&str,file); D: char str = "Hello World"; fputs(str,file);
- 给定一个java程序的代码片断如下，运行后正确的输出结果是（ ）。String s=”hello, world”;String str = s.replace(“,” , ” ”);System.out.println(str); A: hello world; B: hello, world C: HELLO WORLD D: HELLO ,WORLD;
- world = "world"str = 'hello'print str+world 的结果为 A: helloworld B: hello world C: hello "world" D: 语法错误