asp.net - 使用 Watin 选择 Asp.Net DropDownList 值会引发 System.FormatException

Question

我正在尝试使用 Watin 测试 asp:DropDownList，但是当我尝试从呈现的 SelectList 中选择一个选项时，它会抛出 System.FormatException:字符串未被识别为有效的 bool 值。

我的页面代码是:

<%@ Page Title="Home Page" Language="C#" MasterPageFile="~/Site.master" AutoEventWireup="true"
    CodeBehind="Default.aspx.cs" Inherits="TesteSelect._Default" %>

<asp:Content ID="HeaderContent" runat="server" ContentPlaceHolderID="HeadContent">
</asp:Content>
<asp:Content ID="BodyContent" runat="server" ContentPlaceHolderID="MainContent">
   <asp:DropDownList  ID="ddl"
    Width="75px" runat="server">

    <asp:ListItem Text="Yes" Value="true" Selected="true"></asp:ListItem>
    <asp:ListItem Text="No" Value="false"></asp:ListItem>
    </asp:DropDownList>
</asp:Content>

我的测试是:

using NUnit.Framework;
using WatiN.Core;

namespace Test
{
    [TestFixture]
    public class ATest
    {
        [Test]
        public void Should_be_able_to_select_yes_from_ddl()
        {
            using( var browser = new IE())
            {
                browser.GoTo(Properties.Settings.Default.ServerAddress + "Default.aspx");
                SelectList ddl = browser.SelectList(Find.ById("MainContent_ddl"));
                ddl.Option("Yes").Select();

                Assert.That(ddl.SelectedItem.Equals("Yes"));
            }
        }
        [Test]
        public void Should_be_able_to_select_no_from_ddl()
        {
            using (var browser = new IE())
            {
                browser.GoTo(Properties.Settings.Default.ServerAddress + "Default.aspx");
                SelectList ddl = browser.SelectList(Find.ById("MainContent_ddl"));
                ddl.Option("No").Select();

                Assert.That(ddl.SelectedItem.Equals("No"));
            }
        }
    }
}

“否”测试顺利通过，但"is"测试因该异常和此堆栈跟踪而失败:

ATest.Should_be_able_to_select_yes_from_ddl : FailedSystem.FormatException : String was not recognized as a valid Boolean. at System.Boolean.Parse(String value) at WatiN.Core.Option.setSelected(Boolean value, Boolean WaitForComplete) at WatiN.Core.Option.Select() at Test.ATest.Should_be_able_to_select_yes_from_ddl() in ATest.cs: line 16

查看此处提供的源代码 => http://watin.svn.sourceforge.net/viewvc/watin/trunk/src/Core/Option.cs?revision=1194&view=markup

我可以看到错误发生在第 136 行的这段代码段中:

...
134             private void setSelected(bool value, bool WaitForComplete)
135                 {
136                     if (bool.Parse(GetAttributeValue("selected")) == value) return;
137 
138             SetAttributeValue("selected", value.ToString().ToLowerInvariant());
139                     if (WaitForComplete)
140                     {
141                         ParentSelectList.FireEvent("onchange");
142                     }
143                     else
144                     {
145                         ParentSelectList.FireEventNoWait("onchange");
146                     }
147                 }

当我查看生成的 HTML 时，这是有道理的，因为这就是呈现的内容:

<select name="ctl00$MainContent$ddl" id="MainContent_ddl" style="width:75px;">
    <option selected="selected" value="true">Yes</option>
    <option value="false">No</option>

</select>

因此它无法将“selected”解析为 bool 值，这是有道理的。我该如何度过这个难关？

Answer 1

<asp:Content ID="BodyContent" runat="server" ContentPlaceHolderID="MainContent">
<asp:DropDownList  ID="ddl" Width="75px" runat="server">
    <asp:ListItem Text="Yes" Value="1" Selected="true"></asp:ListItem>
    <asp:ListItem Text="No" Value="0"></asp:ListItem>
</asp:DropDownList>

试试这个，让我知道会发生什么。