vue.js 动态改变css

<template>
  <div :style="{ color: activeColor, fontSize: fontSize + 'px' }">
    Hello, Vue!
  </div>
</template>

<script>
export default {
  data() {
    return {
      activeColor: 'red',
      fontSize: 30
    };
  }
};
</script>

<template>
  <div :class="{ active: isActive, 'text-danger': hasError }">
    Hello, Vue!
  </div>
</template>

<script>
export default {
  data() {
    return {
      isActive: true,
      hasError: false
    };
  }
};
</script>

<style>
.active {
  color: green;
}
.text-danger {
  color: red;
}
</style>

<template>
  <div :style="dynamicStyle">
    Hello, Vue!
  </div>
</template>

<script>
export default {
  data() {
    return {
      isActive: true
    };
  },
  computed: {
    dynamicStyle() {
      return {
        color: this.isActive ? 'green' : 'red',
        fontSize: this.isActive ? '30px' : '16px'
      };
    }
  }
};
</script>

<template>
  <div :style="getDynamicStyle()">
    Hello, Vue!
  </div>
</template>

<script>
export default {
  data() {
    return {
      isActive: true
    };
  },
  methods: {
    getDynamicStyle() {
      return {
        color: this.isActive ? 'green' : 'red',
        fontSize: this.isActive ? '30px' : '16px'
      };
    }
  }
};
</script>