district

gistfile1.coffee

@RegionUtils =
  init: (seed = [], region = '.region') ->
    $(region).each ->
      selects = $('select', this)
      selects.unbind('change') # 避免多次绑定change事件
      selects.change ->
        $this = this
        select_index = selects.index($this) + 1 
        select = selects.eq(select_index)
        if $(this).val() and select[0]
          $.get "/district/" + $(this).val(), (data) ->
            result = eval(data)
            options = select[0].options
            $("option:gt(0)", select).remove()
            $.each result, (i, item) -> options.add new Option(item[0], item[1])
            value = seed[select_index]
            select.val(value).change() if value # 级联回显

这个方法有两个作用:

1. 普通用法,级联选择
2. 当所有下拉框的值已经有了,需要回显时,级联选中它们(会用到传入的seed种子值)