创建一个 Javascript 函数，它生成一个随机字符 id，其中包含给定输入长度的字母和数字

Question

I have completed a JavaScript course and now I am stuck with first Hands-on problem. The question is "How to generate Random Character id"

Review below screen:

HTML code

JavaScript Code.

Error message

Please let me know your suggestions

Thanks

The code I used after few suggestions is as below:

function stringGen(yourNumber){
  var text = "";
  var possible = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";

  for (var i = 0; i < yourNumber; i++)
    text += possible.charAt(Math.floor(Math.random() * possible.length));

 return text;
}

stringGen(10);

I get the below error when I test the code in Node.js in Hackerrank

09 10 2018 06:15:13.648:INFO [karma]: Karma v1.7.1 server started at http://0.0.0.0:9876/                                                      
09 10 2018 06:15:13.651:INFO [launcher]: Launching browser jsdom with unlimited concurrency                                                    
09 10 2018 06:15:13.656:INFO [launcher]: Starting browser jsdom                                                                                
09 10 2018 06:15:13.828:INFO [Node.js (linux; U; rv:v8.9.4)]: Connected on socket 1L0-mKrQnWEv092UAAAA with id 34735969                        
Node.js (linux; U; rv:v8.9.4) Random string checking random number FAILED                                                                      
        Expected 0 to be 4.                                                                                                                    
            at UserContext.<anonymous> (test/index_test.js:17:33)                                                                              
Node.js (linux; U; rv:v8.9.4) Random string comparing random numbers FAILED                                                                    
        Expected true to be false.                                                                                                             
            at UserContext.<anonymous> (test/index_test.js:26:16)                                                                              
Node.js (linux; U; rv:v8.9.4): Executed 2 of 2 (2 FAILED) ERROR (0.031 secs / 0.016 secs)                                                      
npm ERR! Test failed.  See above for more details.  

Answer 1

function stringGen(){
  var text = "";
  var possible = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";
  var x = document.getElementById("num").value;
  for (var i = 0; i < x; i++)
    text += possible.charAt(Math.floor(Math.random() * possible.length));

  return text;
}

Answer 2

function stringGen(yourNumber){
  var text = "";
  var possible = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";

  for (var i = 0; i < yourNumber; i++)
    text += possible.charAt(Math.floor(Math.random() * possible.length));

  return text;
}

call Function stringGen(8)

it will generate random string

Answer 3

This worked for me.

function stringGen()
{
   //Type your code here.
   var length = document.getElementById('num').value;
   var result           = '';
   var characters       = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789';
   var charactersLength = characters.length;
   for ( var i = 0; i < length; i++ ) {
      result += characters.charAt(Math.floor(Math.random() * charactersLength));
   }
   document.getElementById("result").innerHTML= result;
   return result;
}

Answer 4

Alright, so I updated my answer. I hope this works for you. Happy coding and welcome to SO :)

 const makeid = () => { let chars = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789"; let id = ""; let num = document.getElementById('input_id').value; for (let i = 0; i < num; i++) { id += chars.charAt(Math.floor(Math.random() * chars.length)); document.getElementById('info1').innerHTML = id; document.getElementById('info2').innerHTML = id.length; } }

 #info1 { color: green; font-weight: bold; letter-spacing: 1px; } #info2 { color: red; font-weight: bold; }

 <input type="number" id="input_id" value=""> <input type="button" value="Submit" onclick="makeid()" /> <div>Your unique id is: <span id="info1"></span> </div> <div>The length of your id is: <span id="info2"></span> </div>

Answer 5

function stringGen(yourNumber){
  var text = "";
  var possible = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";

  for (var i = 0; i < yourNumber; i++)
    text += possible.charAt(Math.floor(Math.random() * possible.length));

 document.getElementById("result").innerHTML= text;
}

Answer 6

Answer

    function stringGen()
{
    var num = document.getElementById('num').value;
   //  alert(num);
         var text = "";
  var possible = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";

  for (var i = 0; i < num; i++)
    text += possible.charAt(Math.floor(Math.random() * possible.length));

 //alert(text);
 document.getElementById('result').innerHTML = text;
  return text;
}

Answer 7

{   
    var c = document.getElementById("num").value;
    let random_string = '';
    let random_ascii;
    let low = 65;
    let high = 90
    for(let i = 0; i < c; i++) {
        random_ascii = Math.floor((Math.random() * (high - low)) + low);
        random_string += String.fromCharCode(random_ascii)
    }
    return random_string
}