Question

在下面的代码中，我想知道如何识别正在执行的类，以便通过应用switch case来个性化它。我试过检查Param T，但它对我没用。

提前致谢！

ExecuteCalculationsWith<RoofMaterialQuantityCalculator>();
ExecuteCalculationsWith<WallMaterialQuantityCalculator>();
ExecuteCalculationsWith<CurtainWallPanelsMaterialQuantityCalculator>();
ExecuteCalculationsWith<FloorMaterialQuantityCalculator>();

private void ExecuteCalculationsWith<T>() where T : MaterialQuantityCalculator, new()
{
    T calculator = new T();
    calculator.SetDocument(m_doc);
    calculator.CalculateMaterialQuantities();

    switch (typeof(T))
    {
        case RoofMaterialQuantityCalculator:
            calculator.InsertDataTableintoSQLTableusingSQLBulkCopy();
            break;
        case WallMaterialQuantityCalculator:
            calculator.InsertDataTableintoSQLTable_walls();
            break;
        default:
            break;
    }
}

Answer 1

如果MaterialQuantityCalculator类有一个abstract方法，例如InsertDataTableIntoSqlTable()，然后每个派生计算器实现它，那么你的泛型方法将如下所示，这将是一个更好的解决方案：

private void ExecuteCalculationsWith<T>()
    where T : MaterialQuantityCalculator, new()
{
    T calculator = new T();
    calculator.SetDocument(m_doc);
    calculator.CalculateMaterialQuantities();
    calculator.InsertDataTableIntoSqlTable();
}

public abstract class MaterialQuantityCalculator
{
    public abstract void InsertDataTableIntoSqlTable();

    // rest is omitted for clarity
}

public class RoofMaterialQuantityCalculator : MaterialQuantityCalculator
{
    public override void InsertDataTableIntoSqlTable()
    {
        // Content of InsertDataTableintoSQLTableusingSQLBulkCopy() method comes here
    }

    // rest is omitted for clarity
}

public class WallMaterialQuantityCalculator : MaterialQuantityCalculator
{
    public override void InsertDataTableIntoSqlTable()
    {
        // Content of InsertDataTableintoSQLTable_walls() method comes here
    }

    // rest is omitted for clarity
}

Answer 2

您可以使用typeof运算符。但你不能在switch个实例上Type _{（您可能 switch在Name个实例的Type属性上，但我不建议这样做，因为它＆＃39;不可靠/可维护/可重构）}

尝试这样：

private void ExecuteCalculationsWith<T>() where T : MaterialQuantityCalculator, new()
{
    T calculator = new T();
    calculator.SetDocument(m_doc);
    calculator.CalculateMaterialQuantities();       

    Type t = typeof(T);
    if (t == typeof(RoofMaterialQuantityCalculator))
        calculator.InsertDataTableintoSQLTableusingSQLBulkCopy();
    else if (t == typeof(WallMaterialQuantityCalculator))
        calculator.InsertDataTableintoSQLTable_walls();
}

在执行期间个性化从抽象类派生的类

2 个答案: