通常一个典型的asp.net控件至少会用ViewState存储一些属性,以便于在页面postback后不用重新设置。在这篇文章里我将介绍如何为控件写
单元测试,以确保一个属性被正确的保存在ViewState里。
为了演示,我写了一个简单的控件。
namespace Eilon.Sample.Controls { using System; using System.Web.UI; public class NewLabel : Control { public string Text { get { string s = ViewState["Text"] as string; return s ?? String.Empty; } set { ViewState["Text"] = value; } } protected override void Render(HtmlTextWriter writer) { writer.Write(Text); } } }
|
这个控件只是简单的将它唯一的属性Text输出。
好的,让我们写一个简单的单元测试,以确保这个控件正确的工作。
namespace Eilon.Sample.Controls.Test { using System; using System.IO; using System.Web.UI; using Microsoft.VisualStudio.TestTools.UnitTesting; [TestClass] public class NewLabelTest { [TestMethod] public void TextReturnsEmptyStringDefault() { NewLabel label = new NewLabel(); Assert.AreEqual(String.Empty, label.Text, "Default text should be empty string (not null)"); } [TestMethod] public void GetSetText() { const string value = "Some Text"; NewLabel label = new NewLabel(); label.Text = value; Assert.AreEqual(value, label.Text, "Property value isn't the same as what we set"); } [TestMethod] public void RenderEmpty() { NewLabel label = new NewLabel(); Assert.AreEqual(String.Empty, GetRenderedText(label), "Shouldn't have rendered anything"); } [TestMethod] public void RenderWithText() { const string value = "Some Text"; NewLabel label = new NewLabel(); label.Text = value; Assert.AreEqual(value, GetRenderedText(label), "Should have rendered the text"); } private static string GetRenderedText(Control c) { HtmlTextWriter writer = new HtmlTextWriter(new StringWriter()); c.RenderControl(writer); return writer.InnerWriter.ToString(); } } }
|