利用反射实现WSDL实体与自定义实体之间的转换

场景：

    WebService中的传入/传出参数是一个字段非常多的一个对象，我们往往是在业务逻辑层来引用WebService，而值是从页面层传入的，因此需要自己定义一个实体，来实现页面层往业务逻辑层之间的传值。

如果两个实体之间字段非常多的话，可以利用反射来实现两个实体之间的转换。

 

首先，我们自定义一个Attribute，用于表示实体中某个属性，在WSDL中的名称（WSDL中的属性名称与自定义的不一定一致，比如用Java开发的WebService，在C#中调用，属性的编码规范不一样）：

[AttributeUsage(AttributeTargets.All, AllowMultiple=true)]
public class WSDLFieldNameAttribute : Attribute
{
    public string FieldName
    {
        get;
        set;
    }

    public Type FieldType
    {
        get;
        set;
    }

    public WSDLFieldNameAttribute(string Field)
    {
        FieldName = Field;
        FieldType = typeof(string);
    }
    public WSDLFieldNameAttribute(string Field, Type type)
    {
        FieldName = Field;
        FieldType = type;
    }
}

使用方法：

[WSDLFieldNameAttribute("fromDate")]
[Description("开始日期，格式“yyyyMMdd”")]
public string FromDate
{
    get;
    set;
}

转换类：

public static class WSDLFieldMappingUtil
{
    /// <summary>
    /// fill wsdl entity from entity
    /// </summary>
    /// <param name="wsdlObject"></param>
    /// <param name="entity"></param>
    public static void FillInWSDLEntity(object wsdlObject, object entity)
    {
        Type wsdlType = wsdlObject.GetType();
        Type entityType = entity.GetType();

        PropertyInfo wsdlProperty;
        PropertyInfo[] pi = entityType.GetProperties();

        foreach (PropertyInfo entityProperty in pi)
        {
            WSDLFieldNameAttribute[] myAttribute = (WSDLFieldNameAttribute[])entityProperty.GetCustomAttributes(typeof(WSDLFieldNameAttribute), false);
            if (myAttribute.Length == 0)
            {
                continue;
            }

            if (entityProperty.PropertyType.IsEnum)
            {
                if (myAttribute.Length == 1 && myAttribute[0].FieldType == typeof(string))
                {
                    wsdlProperty = wsdlType.GetProperty(myAttribute[0].FieldName);
                    if (wsdlProperty == null)
                        continue;

                    var value = entityProperty.GetValue(entity, null);
                    if (value != null)
                    {
                        wsdlProperty.SetValue(wsdlObject, EnumAttributeHelper.GetSqlByEnum(value), null);
                    }
                }
                else
                {
                    throw new Exception(string.Empty);
                }
            }
            else
            {
                wsdlProperty = wsdlType.GetProperty(myAttribute[0].FieldName);
                if (wsdlProperty == null)
                    continue;

                var value = entityType.GetProperty(entityProperty.Name).GetValue(entity, null);
                if (value != null)
                {
                    if (wsdlProperty.PropertyType != entityProperty.PropertyType)
                    {
                        if (wsdlProperty.PropertyType.IsEnum)
                        {
                            value = Enum.Parse(wsdlProperty.PropertyType, value.ToString());
                        }
                        else if (entityProperty.PropertyType == typeof(DateTime))
                        {
                            value = ((DateTime)value).ToString("yyyyMMdd");
                        }
                        else
                        {
                            value = Convert.ChangeType(value, wsdlProperty.PropertyType);
                        }
                    }

                    wsdlProperty.SetValue(wsdlObject, value, null);
                }
                else
                {
                    if (wsdlProperty.PropertyType == typeof(string))
                    {
                        wsdlProperty.SetValue(wsdlObject, "", null);
                    }
                }
            }
        }
    }

    /// <summary>
    /// fill entity from wsdl entity
    /// </summary>
    /// <param name="wsdlObject"></param>
    /// <param name="entity"></param>
    public static void FillInEntityFromWSDLObject(object entity, object wsdlObject)
    {
        if (wsdlObject == null)
            return;

        Type wsdlType = wsdlObject.GetType();
        Type entityType = entity.GetType();

        PropertyInfo wsdlProperty;
        PropertyInfo[] pi = entityType.GetProperties();

        foreach (PropertyInfo entityProperty in pi)
        {
            WSDLFieldNameAttribute[] myAttribute = (WSDLFieldNameAttribute[])entityProperty.GetCustomAttributes(typeof(WSDLFieldNameAttribute), false);
            if (myAttribute.Length == 0)
            {
                continue;
            }

            if (entityProperty.PropertyType.IsEnum)
            {
                if (myAttribute.Length == 1 && myAttribute[0].FieldType == typeof(string))
                {
                    wsdlProperty = wsdlType.GetProperty(myAttribute[0].FieldName);
                    if (wsdlProperty == null)
                        continue;

                    var value = wsdlProperty.GetValue(wsdlObject, null);
                    if (value != null && value.ToString() != "")
                    {
                        entityProperty.SetValue(entity, EnumAttributeHelper.GetEnumBySqlValue(entityProperty, value.ToString()), null);
                    }
                }
                else
                {
                    throw new Exception(string.Empty);
                }
            }
            else
            {
                wsdlProperty = wsdlType.GetProperty(myAttribute[0].FieldName);
                if (wsdlProperty == null)
                    continue;

                var value = wsdlProperty.GetValue(wsdlObject, null);
                if (value != null)
                {
                    if (value.ToString() == "")
                    {
                        if (entityProperty.PropertyType == typeof(string))
                        {
                            entityProperty.SetValue(entity, value, null);
                        }
                        continue;
                    }

                    if (wsdlProperty.PropertyType != entityProperty.PropertyType)
                    {
                        if (entityProperty.PropertyType == typeof(DateTime))
                        {
                            if (value.ToString().Length == 8)
                            {
                                value = value.ToString().Substring(0, 4) + "-" + value.ToString().Substring(4, 2) + "-" + value.ToString().Substring(6, 2);
                            }
                        }
                        value = Convert.ChangeType(value, entityProperty.PropertyType);
                    }

                    entityProperty.SetValue(entity, value, null);
                }
            }
        }
    }
}

 

上面代码需要注意的是，在某些时候，某个属性在传输的时候是以字符串的形式传输或者存储的，而在我们自定义的实体中，为了提高代码的可读性，而使用枚举

如：在数据库中存储的值分别是：O,C,P,D

public enum DcoumentStatusEnum
{
    [SqlValue("O")]
    Open = 0,
    [SqlValue("C")]
    Close = 1,
    [SqlValue("P")]
    Paid = 2,
    [SqlValue("D")]
    Delivered = 3
}

因此需要对枚举做些特殊处理，自定义一个SqlValueAttribute:

[AttributeUsage(AttributeTargets.All)]
public class SqlValueAttribute : Attribute
{
    public string Text
    {
        get;
        set;
    }
    public SqlValueAttribute(string text)
    {
        Text = text;
    }
}

 

利用反射，根据SqlValue获取枚举，或者根据枚举获取SqlValue，性能可能会比较低，暂时也没想出什么好的办法。

public static object GetEnumBySqlValue(PropertyInfo pInfo, string sqlValue)
{
    FieldInfo[] pi = pInfo.PropertyType.GetFields();
    foreach (FieldInfo p in pi)
    {
        SqlValueAttribute[] myAttribute = (SqlValueAttribute[])p.GetCustomAttributes(typeof(SqlValueAttribute), false);
        foreach (SqlValueAttribute m in myAttribute)
        {
            if (m.Text == sqlValue.Trim())
            {
                string a = p.ToString();
                return Enum.Parse(pInfo.PropertyType, p.Name);
            }
        }
    }
    return null;
}

public static string GetSqlByEnum(object enumValue)
{
    FieldInfo[] pi = enumValue.GetType().GetFields();

    foreach (FieldInfo p in pi)
    {
        if (p.Name == enumValue.ToString())
        {
            SqlValueAttribute[] myAttribute = (SqlValueAttribute[])p.GetCustomAttributes(typeof(SqlValueAttribute), false);
            foreach (SqlValueAttribute m in myAttribute)
            {
                return m.Text;
            }
        }
    }
    return null;
}