Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Welcome To Ask or Share your Answers For Others

Categories

0 votes
398 views
in Technique[技术] by (71.8m points)

javascript prompt number and continue prompting if answer is wrong

I need prompt the visitor for an integer between 1 and 100 and to continue prompting until a valid number is entered.

Here is what I have:

<script>

var number = parseInt(prompt("Please enter a number from 1 to 100", ""));

if (number < 100) {
    document.write("Your number (" + number + ") is matches requirements", "");
} else if (isNaN(number)) {
    parseInt(prompt("It is not a number. Please enter a number from 1 to 100", ""));
} else {
    parseInt(prompt("Your number (" + number + ") is above 100. Please enter a number from 1 to 100", ""));
}

</script>

It recognizes the number but fails to re-ask when the number is wrong. Can you please help me and explain what you added?

Thank you very much.

See Question&Answers more detail:os

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome To Ask or Share your Answers For Others

1 Reply

0 votes
by (71.8m points)

Something like this should do the trick:

do{
    var selection = parseInt(window.prompt("Please enter a number from 1 to 100", ""), 10);
}while(isNaN(selection) || selection > 100 || selection < 1);

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
OGeek|极客中国-欢迎来到极客的世界,一个免费开放的程序员编程交流平台!开放,进步,分享!让技术改变生活,让极客改变未来! Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Click Here to Ask a Question

...