Function setSelected

packages/runtime-dom/src/directives/vModel.ts:246–281

(el: HTMLSelectElement, value: any)

}

function setSelected(el: HTMLSelectElement, value: any) {
  const isMultiple = el.multiple
  const isArrayValue = isArray(value)
  if (isMultiple && !isArrayValue && !isSet(value)) {
    __DEV__ &&
      warn(
        `<select multiple v-model> expects an Array or Set value for its binding, ` +
          `but got ${Object.prototype.toString.call(value).slice(8, -1)}.`,
      )
    return
  }

  for (let i = 0, l = el.options.length; i < l; i++) {
    const option = el.options[i]
    const optionValue = getValue(option)
    if (isMultiple) {
      if (isArrayValue) {
        const optionType = typeof optionValue
        // fast path for string / number values
        if (optionType === 'string' || optionType === 'number') {
          option.selected = value.some(v => String(v) === String(optionValue))
        } else {
          option.selected = looseIndexOf(value, optionValue) > -1
        }
      } else {
        option.selected = value.has(optionValue)
      }
    } else if (looseEqual(getValue(option), value)) {
      if (el.selectedIndex !== i) el.selectedIndex = i
      return
    }
  }
  if (!isMultiple && el.selectedIndex !== -1) {
    el.selectedIndex = -1
  }
}

// retrieve raw value set via :value bindings
function getValue(el: HTMLOptionElement | HTMLInputElement) {