setAjaxOptions

setAjaxOptions是我们在weui.me.js中扩展的一个函数，用于根据后台数据动态生成列表项目，语法：

setAjaxOptions(SelectID, URL, ID1, ID2, ..., asyn)

例如：

setAjaxOptions('品牌','getBrands.htm','国家',false)

表示将"国家"输入框的值，传递给后台的网页getBrands.htm，为"品牌"输入框生成列表项目 ，注意这里的"国家"和"品牌"，都是输入框的ID。

后台的处理代码可以非常的简单，例如根据收到的国家名称，从数据表提取品牌，回传给客户端即可：

Dim pps As String = DataTables("汽车").GetComboListString("品牌","国家='" & e.PostValues("国家") & "'")
e.WriteString(pps)

示例一

假定后台有个名为"汽车"的数据表：

前台的录入界面如下图，希望选择不同的国家后，能自动根据后台数据表的内容，列出该国的汽车品牌供选择：

看起来比较复杂，其实非常简单，HttpRequest事件代码：

Select Case e.Path
    Case "test.htm"
        Dim wb As New weui
        wb.AddForm("","form1","test.htm")
        With wb.AddInputGroup("form1","ipg1","动态列表")
            With .AddSelect("国家","国家","|中国|德国|日本")
                .Attribute = "onchange=""setAjaxOptions('品牌','getBrands.htm','国家',false)"""
            End With
            .AddSelect("品牌","品牌","")
        End With
        With wb.AddButtonGroup("form1","btg1",True)
            .Add("btn1", "确定", "submit")
        End With
        e.WriteString(wb.Build) '生成网页
    Case  "getBrands.htm"
        Dim pps As String = DataTables("汽车").GetComboListString("品牌","国家='" & e.PostValues("国家") & "'")
        e.WriteString(pps)
End Select

示例二

根据setAjaxOptions可以做出级联列表的效果，假定后台有个表A：

希望前台的输入页面，选择不同的型号，能自动列出对应的规格供选择，选择某个规格后，还能自动列出对应的颜色供选择：

HttpRequest事件代码：

Select Case e.Path
    Case "test.htm"
        Dim wb As New weui
        wb.AddForm("","form1","test.htm")
        With wb.AddInputGroup("form1","ipg1","动态列表")
            With .AddSelect("xh","型号","|" & DataTables("表A").GetComboListString("型号"))
                .Attribute = "onchange=""setAjaxOptions('gg','getProducts.htm','xh',false)"""
            End With
            With .AddSelect("gg","规格","")
                .Attribute = "onchange=""setAjaxOptions('ys','getProducts.htm','xh','gg',false)"""
            End With
            .AddSelect("ys","颜色","")
        End With
        With wb.AddButtonGroup("form1","btg1",True)
            .Add("btn1", "确定", "submit")
        End With
        e.WriteString(wb.Build) '生成网页
    Case  "getProducts.htm"
        Dim vals As String
        If e.PostValues.Count = 1 Then
            vals  = "|" & DataTables("表A").GetComboListString("规格","型号='" & e.PostValues("xh") & "'")
        ElseIf e.PostValues.Count = 2 Then
            Dim Filter As String = "型号='" & e.PostValues("xh") & "' And 规格='" & e.PostValues("gg") & "'"
            vals = "|" & DataTables("表A").GetComboListString("颜色", Filter)
        End If
        e.WriteString(vals)
End Select

注意这里型号输入框的ID是"xh"，规格输入框的id是"gg"，setAjaxOptions通过ID来提交输入框的值，例如：

setAjaxOptions('ys','getProducts.htm','xh','gg',false)

服务端也是通过ID来获取对应输入框的值：e.PostValues("xh")