Vue element-ui <el-table-column> formatter – how to display html?

Question

How to return html formatted cell value?

I want to get custom formatted value (with html or other components) with <el-table-column> formatter.

<el-table :data="data">
  <el-table-column v-for="(column, index) in columns" 
                   :key="index" :label="column.label" 
                   :formatter="column.formatter">
  </el-table-column>
</el-table>

data() {
  return {
    columns: [
      {
        label: 'Created at',
        formatter: (row, col, value, index) => {
          return `<span class="date">${value}</span>`
        }
      },
      // edit:
      {
        label: 'Address',
        formatter: (row, col, value, index) => {
          return `<mini-map :data="${row}"></mini-map>`
        }
      }
      // other dynamic columns...
    ]
  }
}

But cell content is displayed as escaped html string. Is there any possibility to force html?

EPIC EDIT: I added an answer with a solution.

Answer 1

Ok, after a few hours of brainstorming I found pretty nice solution. I'm putting it here for others - I hope this helps somebody.

Value displayed in custom column can be:

• simple string (prop)

• formatted string (safe, without any html or components, via original formatter)

• customized value (html, component, also safe!)

In order to achieve this, I had to create custom formatter components, which I put in folder i.e. /TableFormatters/

For this purpose, there is simple functional component DatetimeFormatter that display date-time with icon.

TableFormatters/DatetimeFormatter.vue

<template functional>
  <span>
    <i class="icon-date"></i> {{ props.row[props.column] }}
  </span>
</template>

<script>
  export default {
    name: 'DatetimeFormatter',
  }
</script>

Here come's columns configuration:

import DatetimeFormatter from './TableFormatters/DatetimeFormatter'
// ...
data() {
  return {
    data: [/*...*/],
    columns: [
      name: {
        label: 'Name',
      },
      state: {
        label: 'State',
        formatter: row => {
            return 'State: '+row.state__label
        }
      },
      created_at: {
        label: 'Created at',
        formatter: DatetimeFormatter
      }
    ]
  }
}

Now it's time to define <el-table>:

<el-table :data="data">
  <el-table-column 
    v-for="(column, index) in columns" 
    :key="index" 
    :label="columns[column] ? columns[column].label : column"
    :prop="column"
    :formatter="typeof columns[column].formatter === 'function' ? columns[column].formatter : null">
    <template #default="{row}" v-if="typeof columns[column].formatter !== 'function'">
      <div v-if="columns[column].formatter"
        :is="columns[column].formatter" 
        :row="row" 
        :column="column">
      </div>
      <template v-else>
        {{ row[column] }}
      </template>
    </template>
  </el-table-column>
</el-table>

This works like a charm. What's going on here with formatter? First we check if the formatter is set as a function. If so, the native <el-table-column> formatter takes the control, because <template #default={row}> will not be created. Otherwise formatter component will be created (via :is attribute). However, it there is no formatter, the plain value for a row will be shown.

Answer 2

If you want to render custom HTML for a <el-table-column>, you will need to make use of the custom column template functionality, rather than the :formatter prop. It's going to look something like this:

<el-table :data="data">
  <el-table-column
    v-for="(column, index) in columns" 
    :key="index"
    :label="column.label"
  >
    <template slot-scope="scope">
      <span class="date">{{ scope.row.value }}</span>
    </template>
  </el-table-column>
</el-table>

In the general case, you can make use of the v-html directive if you need to render unescaped HTML. There are some security implications involved, so make sure you understand those before reaching for v-html.

Essentially, it boils down to this: never use v-html to render content that was provided by the user.