专注前端素材！
源代码：
点击运行
<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title>素材8网教程(study.sucai8.cn)</title> </head> <body> <script> var txt = "Hello World!"; document.write("<p>" + txt.length + "</p>"); var txt="ABCDEFGHIJKLMNOPQRSTUVWXYZ"; document.write("<p>" + txt.length + "</p>"); </script> </body> </html>
运行结果