How to add dynamically attribute in VueJs

As pointed out, you don't need dynamic attributes in your case.

But well, you asked if it is possible, and the answer is yes. You can have dynamic attributes, as of 2.6.0.

Example:

<a v-bind:[attributeName]="whatever">

It is documented here

I am trying to figure out how to set the attribute of the html tags from the array value dynamically when using the Vue v-for loop.

What I am going to show:

Example

1. There are 3 div elements with different background colors from array value(not static).

2. Each divs have a input tag and change the value when the user input value

   • The first div's input converts lowercase to uppercase.
   • second represents the mood, if enter 'happy', present 'good'. if enter 'sad', output 'bad'
   • The third div input doubles the input value.
   {{ box.outputData }} Rounded Box

   new Vue({
    el: "#app",
     data: {
       isRounded: false,
         boxes: [
           {
             inputData: "",
             outputData: "",
             color: "green",
             operation: "uppercase"
           },
           {
             inputData: "",
             outputData: "",
             color: "red",
             operation: "feeling"
           },
           {
             inputData: "",
             outputData: "",
             color: "blue",
             operation: "multiple"
           }
         ],
         feeling: {
           good: ["happy", "joyful", "calm"],
           bad: ["sad", "mad", "depressed"]
         }
     },
     methods: {
       toggle: function(todo){
           todo.done = !todo.done
       }
     },
     watch: {
       boxes: {
         deep: true,
         immediate: true,
         handler: function(val) {
           this.boxes.map(box => {
             if (box.operation === "uppercase")
               box.outputData = box.inputData.toUpperCase();
             else if (box.operation === "feeling") {
               box.outputData = this.feeling.good.includes(box.inputData)
                 ? "GOOD"
                 : this.feeling.bad.includes(box.inputData)
                 ? "BAD"
                 : "";
             } else if (box.operation === "multiple") {
               if (box.inputData == "") box.outputData = "";
               else box.outputData = parseInt(box.inputData) * 2;
             }
           });
         }
       }
     },
     mounted() {
       for (var i = 0; i < this.numBox; i++) {
         this.boxValue[i] = "";
         this.bxData[i] = "";
       }
     },
   })
   
   
   
   .clearfix{
    clear: both;
   }
   .full-width{
     width:100%;
   }
   input {
     background: transparent;
     text-decoration: underline;
     color: white;
     border: none;
     text-align: center;
     font-size:30px;
   }
   .box {
     float:left;
     color: white;
     width: 24%;
     margin-right: 1%;
     padding: 20px;
     background: blue;
     height: 100px;
   }
   .box-output {
     width: 100%;
     text-align: center;
     font-size:30px;
   }
   .box-rounded {
     border-radius: 50px;
   }
   

You can bind it to a variable using v-bind:disabled="foo" or :disabled="foo" for short:

<textfield label="Name" value.sync="el.name" :disabled="myVar">

Then in Vue you can just set this.myVar = true and it will disable the input.

Edit: add this to your template:

<template>
  <input type="text" :disabled="disabled" :placeholder="placeholder" v-model="value">
</template>