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为什么我的Type.GetFields(BindingFlags.Instance | BindingFlags.Public)不起作用?

reflection .net c#

granadaCoder · 技术社区 · 15 年前

FieldInfo[] publicFieldInfos =
    t.GetFields(BindingFlags.Instance | BindingFlags.Public);

什么也没回来。

注意:我试图得到抽象类的属性以及混凝土类(并读取属性)。

MSDN示例使用2个标志 (BindingFlags.Instance | BindingFlags.Public) 但我下面的迷你继承示例却没有。

private void RunTest1()
{
    try
    {
        textBox1.Text = string.Empty;

        Type t = typeof(MyInheritedClass);

        //Look at the BindingFlags *** NonPublic ***

        int fieldCount = 0;

        while (null != t)
        {
            fieldCount += t.GetFields(BindingFlags.Instance |
            BindingFlags.NonPublic).Length;

            FieldInfo[] nonPublicFieldInfos = t.GetFields(BindingFlags.Instance |
            BindingFlags.NonPublic);

            foreach (FieldInfo field in nonPublicFieldInfos)
            {
                if (null != field)
                {
                    Console.WriteLine(field.Name);
                }
            }

            t = t.BaseType;
        }

        Console.WriteLine("\n\r------------------\n\r");

        //Look at the BindingFlags *** Public ***

        t = typeof(MyInheritedClass);

        FieldInfo[] publicFieldInfos = t.GetFields(BindingFlags.Instance |
        BindingFlags.Public);

        foreach (FieldInfo field in publicFieldInfos)
        {
            if (null != field)
            {
                Console.WriteLine(field.Name);

                object[] attributes = field.GetCustomAttributes(t, true);

                if (attributes != null && attributes.Length > 0)
                {
                    foreach (Attribute att in attributes)
                    {
                        Console.WriteLine(att.GetType().Name);
                    }
                }
            }
        }
    }
    catch (Exception ex)
    {
        ReportException(ex);
    }
}

private void ReportException(Exception ex)
{
    Exception innerException = ex;

    while (innerException != null)
    {
        Console.WriteLine(innerException.Message + System.Environment.NewLine +
        innerException.StackTrace + System.Environment.NewLine +
        System.Environment.NewLine);

        innerException = innerException.InnerException;
    }
}

public abstract class MySuperType
{
    public MySuperType(string st)
    {
        this.STString = st;
    }

    public string STString
    {
        get;
        set;
    }

    public abstract string MyAbstractString { get; set; }
}

public class MyInheritedClass : MySuperType
{
    public MyInheritedClass(string ic)
        : base(ic)
    {
        this.ICString = ic;
    }

    [Description("This is an important property"), Category("HowImportant")]
    public string ICString
    {
        get;
        set;
    }

    private string _oldSchoolPropertyString = string.Empty;

    public string OldSchoolPropertyString
    {
        get { return _oldSchoolPropertyString; }
        set { _oldSchoolPropertyString = value; }
    }

    [Description("This is a not so importarnt property"),
    Category("HowImportant")]
    public override string MyAbstractString
    {
        get;
        set;
    }
}

以下是我接受这里的建议后的代码:

private void RunTest1()
{
    try
    {

        textBox1.Text = string.Empty;

        Type t = typeof(MyInheritedClass);


        //Look at the BindingFlags *** NonPublic ***
        int fieldCount = 0;
        while (null != t)
        {
            fieldCount += t.GetFields(BindingFlags.Instance | BindingFlags.NonPublic).Length;

            PropertyInfo[] nonPublicFieldInfos = t.GetProperties(BindingFlags.Instance | BindingFlags.NonPublic);
            foreach (PropertyInfo field in nonPublicFieldInfos)
            {
                if (null != field)
                {
                    Console.WriteLine(field.Name);

                }
            }

            t = t.BaseType;

        }



        Console.WriteLine("\n\r------------------\n\r");



        //Look at the BindingFlags *** Public ***
        t = typeof(MyInheritedClass);
        PropertyInfo[] publicFieldInfos = t.GetProperties(BindingFlags.Instance | BindingFlags.Public);

        foreach (PropertyInfo field in publicFieldInfos)
        {
            if (null != field)
            {
                Console.WriteLine(field.Name);
                textBox1.Text += field.Name + System.Environment.NewLine;
                DescriptionAttribute[] attributes = (DescriptionAttribute[])field.GetCustomAttributes(typeof(DescriptionAttribute), false);             

                if (attributes != null && attributes.Length > 0)
                {
                    foreach (Attribute att in attributes)
                    {
                        Console.WriteLine(att.GetType().Name);

                    }
                }
            }
        }
    }
    catch (Exception ex)
    {
        ReportException(ex);
    }

}

private void ReportException(Exception ex)
{



    Exception innerException = ex;
    while (innerException != null)
    {
        Console.WriteLine(innerException.Message + System.Environment.NewLine + innerException.StackTrace + System.Environment.NewLine + System.Environment.NewLine);

    }

}


public abstract class MySuperType
{
    public MySuperType(string st)
    {
        this.STString = st;
    }
    public string STString
    {
        get;
        set;
    }

    public abstract string MyAbstractString {get;set;}

}

public class MyInheritedClass : MySuperType
{
    public MyInheritedClass(string ic)
        : base(ic)
    {
        this.ICString = ic;
    }

    [Description("This is an important property"),Category("HowImportant")]
    public string ICString
    {
        get;
        set;
    }


    private string _oldSchoolPropertyString = string.Empty;
    public string OldSchoolPropertyString
    {
        get { return _oldSchoolPropertyString; }
        set { _oldSchoolPropertyString = value; }
    }


    [Description("This is a not so importarnt property"), Category("HowImportant")]
    public override string MyAbstractString
    {
        get; set;
    }


}

2 回复 | 直到 15 年前

Dan Tao 15 年前

一般来说你不会发现任何非公开领域

public class MyClass {
    private int myField;
    public int MyProperty {
        get { return myField; }
    }
}

领域 myField )是私人的 ( MyProperty )是公开的。

// note: fields -> generally non-public
Type.GetFields(BindingFlags.Instance | BindingFlags.NonPublic)

而对于房地产而言,情况恰恰相反:你很可能从以下项目中获得最大的里程数:

// note: properties -> generally public
Type.GetProperties(BindingFlags.Instance | BindingFlags.Public)

全部的 (公开) 和非公共)特定类型(字段/属性)的成员,您必须使用:

Type.GetFields( // (or GetProperties)
    BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic
)

LukeH 15 年前

也许是因为你在用 GetFields 而且这个类没有任何公共字段:属性和字段是两个不同的东西。

尝试使用 GetProperties 方法而不是 获取字段 .