unit-testing - Visual Studio 2010 单元测试总是给出 NullReferenceException 错误

Question

我正在尝试使用单元测试向导进行单元测试，但我总是得到：

测试方法 TestProject9.Log_InsertMasterTest 抛出异常：
System.NullReferenceException：对象引用未设置为对象的实例。

我的test.cs：

    [TestMethod()]
    [DeploymentItem("Engine.dll")]
    public void Log_InsertMasterTest()
    {
        SkinnedRepairSearch_Accessor target = new SkinnedRepairSearch_Accessor(); // TODO: Initialize to an appropriate value
        int RepairMasterID = 0; // TODO: Initialize to an appropriate value
        int RepairMasterIDOld = 0; // TODO: Initialize to an appropriate value
        int id = 0; // TODO: Initialize to an appropriate value
        string Text = string.Empty; // TODO: Initialize to an appropriate value
        target.Log_InsertMaster(RepairMasterID, RepairMasterIDOld, id, Text);
        Assert.Inconclusive("A method that does not return a value cannot be verified.");
    }

Log_InsertMaster 方法：

protected void Log_InsertMaster(int RepairMasterID, int RepairMasterIDOld, int id, string Text)
{
    SqlConnection myConnection = new SqlConnection(Globals.DatabaseConnectionString);

    SqlCommand myCommand = new SqlCommand("dbo.Repair_LogInsertMaster", myConnection);
    myCommand.CommandType = CommandType.StoredProcedure;

    myCommand.Parameters.Add("@RepairMasterID", SqlDbType.Int).Value = RepairMasterID;
    myCommand.Parameters.Add("@RepairMasterIDold", SqlDbType.Int).Value = RepairMasterIDOld;
    myCommand.Parameters.Add("@DateTime", SqlDbType.DateTime).Value = System.DateTime.Now;
    myCommand.Parameters.Add("@RepairID", SqlDbType.Int).Value = id;
    myCommand.Parameters.Add("@UserSignature", SqlDbType.NVarChar, 200).Value = AdminUser.Signature;
    myCommand.Parameters.Add("@Text", SqlDbType.NVarChar, 200).Value = Text;

    myConnection.Open();
    myCommand.ExecuteNonQuery();
    myConnection.Close();
}

如何不出现此错误？以及如何使用 Unint 测试向导？

异常行：

SkinnedRepairSearch_Accessor target = new SkinnedRepairSearch_Accessor(); // TODO: Initialize to an appropriate value

我尝试了其他公共方法：

[TestMethod()]
public void EmptyTextBoxesTest()
{
    SkinnedRepair target = new SkinnedRepair(); // TODO: Initialize to an appropriate value
    Control parent = null; // TODO: Initialize to an appropriate value
    target.EmptyTextBoxes(parent);
    Assert.Inconclusive("A method that does not return a value cannot be verified.");
}

同样的错误