This article example shares the specific code for JavaScript to generate a 4-digit random verification code for your reference. The specific content is as follows Code: <!doctype html> <html> <head> <meta charset="utf-8"> <title>Generate 4-digit random verification code</title> <style> label{ color:aqua; float:left; font-size: 20px; line-height:2em; } #tex{ display:inline-block; width:50px; height: 25px; float:left; text-align: center; font-size:15px; margin-top:10px; } #showyz{ border:3px solid green; color:blue; width:90px; height:40px; text-align:center; float:left; margin-left:15px; line-height: 2.5em; } #hyz{ background-color:burlywood; border:1px solid burlywood; width:50px; height:20px; float: left; margin-left:20px; margin-top: 10px; margin-right:15px; } #btn{ } </style> </head> <body> <label for="tex">Please enter the verification code:</label><input type="text" id="tex" maxlength="4" autofocus> <div id="showyz"></div> <div id="hyz">Change one</div><br> <input type="button" id="btn" value="Confirm"> </body> <script> //Define an empty array to save 62 codes var codes=[]; //Save the code corresponding to the number into the codes array, the digital code range is [48-57] for(var i=48;i<=57;i++){ codes.push(i); } //Save the codes corresponding to uppercase letters into the codes array, corresponding to the code range [65-90] for(var i=65;i<=90;i++){ codes.push(i); } //Save the codes corresponding to lowercase letters into the codes array, corresponding to the code range [97-122] for(var i=97;i<=122;i++){ codes.push(i); } //Define a method to generate a 62-bit random number as an array subscript, return a random code, and then convert the code into a corresponding number or letter function suiji(){ var arr=[]; //define an array to store 4-bit random numbers for(var i=0;i<4;i++){ var index = Math.floor(Math.random()*(61-0+1)+0); //Generate a random number var char = String.fromCharCode(codes[index]); //Decode arr.push(char); //Store in array arr } return arr.join(""); //Convert the array to a string, separated by spaces, and return } var yzm=suiji();//Call method to return the verification code to yzm//Get the above element var tex=document.getElementById("tex"); var showyz=document.getElementById("showyz"); var hyz = document.getElementById("hyz"); var btn = document.getElementById("btn"); //Write the verification code into the div with id showyzshowyz.innerHTML=yzm; //Realize the function of changing the verification code hyz.onclick=function(){ yzm=suiji(); showyz.innerHTML=yzm; } //Verify the verification code you entered with the random verification code obtained btn.onclick=function(){ var textvalue=tex.value;//Get the input value if(textvalue.toLowerCase()==yzm.toLowerCase()){//Convert all values to lowercase for comparison alert("Verification code input is correct!"); yzm=suiji(); showyz.innerHTML=yzm; tex.value=""; } else{ alert("Verification code input is wrong, please re-enter!"); yzm=suiji(); showyz.innerHTML=yzm; tex.value=""; } } </script> </html> The above is the full content of this article. I hope it will be helpful for everyone’s study. I also hope that everyone will support 123WORDPRESS.COM. You may also be interested in:
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