指令的使用

使用ng-options指令生成的option元素填充select元素

可以使用array或者object类型的数据，用法如下：

• for array data sources:
• • lable for value in array

  • 基本用法：（显示 array 对象的某一个属性值作为下拉名称）

  • 显示更多：同一对象显示更多下拉名称（比如需要显示 o 对象的两个或更多个属性值作为一个下拉列表项）:

    ng-options = ”(o.attr1 + ‘-’ + o.attr2) for o in dataArr “

  • select as lable for value in array

  • select: 是 ng-model 绑定的值

    lable: 是下拉列表显示的值。

  • label group by group for value in array

  • 选项分组（将下拉选项按照 o 对象某一属性分组显示）：

    ng-options = ” (o.attr1 + ‘-’ + o.attr2) group by o.attr3 for o in dataArr “

  • label disable when disable for value in array
  • label group by group for value in array track by trackexpr
  • label disable when disable for value in array track by trackexpr
  • label for value in array | orderBy: orderexpr track by trackexpr (for including a filter with track by)
• for object data sources:
• • label for (key, value) in object
  • select as lable for (key, value) in object
  • label group by group for (key, value) in object
  • label disable when disable for (key, value) in object
  • select as lable group by group for (key, value) in object
  • select as lable disable when disable for (key, value) in object

如何解决ng-options遍历渲染的option第一个为空的情况: <option value="" selected hidden></option>，给ng-model赋初始值即可