JavaScript中有三种原生的弹出框，分别是alert、confirm、prompt。分别表示弹出框、确认框、信息框。
以下是示例代码：
<!DOCTYPE html> <html> <head> <title>JavaScript中的三种弹出框</title> <meta http-equiv="Content-Type" content="text/html; charset=utf-8"/> </head> <body> <input type="submit" value="alert" onclick="alertExample()" /> <input type="submit" value="confirm" onclick="confirmExample()" /> <input type="submit" value="prompt" onclick="promptExample()" /> </body> <script type="text/JavaScript"> function alertExample(){ alert("这是弹出框"); } function confirmExample(){ var r=confirm("按下按钮"); if (r==true){ alert("您按了确认！"); }else if(r==false){ alert("您按了取消！"); } } function promptExample() { var score;//分数 var degree;//等级 score = prompt("你的分数是多少？"); if (score > 100){ degree = '耍我？100分满分！'; }else{ switch (parseInt(score / 10)) { case 0: case 1: case 2: case 3: case 4: case 5: degree = "恭喜你，又挂了！"; break; case 6: degree = "勉强及格"; break; case 7: degree = "凑合，凑合" break; case 8: degree = "不错，不错"; break; case 9: case 10: degree = "高手高手，佩服佩服"; } } alert(degree); } </script> </html>