yfisaboy 2020-01-19
<script type="text/javascript"> document.write("请输入要生成随机数的位数:"); // digit是数字的位数 function runStr(digit){ if(digit=="" || isNaN(digit)){ alert("请输入数字"); }else{ var sourceStr="0,1,2,3,4,5,6,7,8,9,A,B,C,D,E,F,G"; arrStr=sourceStr.split(","); var result=""; //定义变量并初始化 var index=0; for(i=0;i<digit;i++){ index=parseInt(Math.random()*arrStr.length); result+=arrStr[index]; } alert(result); } } </script> <form name="form"> <input type="text" name="digit"/> <input type="button" value="生成" onClick="runStr(form.digit.value)"> </form>