[C#/COMMON] 객체 리스트 특정 객체 속성 값의 집합 구하기 (속성 2개 이상 지정 가능)

■ 객체 리스트에서 특정 객체 속성 값의 집합을 구하는 방법을 보여준다. (속성 2개 이상 지정 가능)

▶ 예제 코드 (C#)


using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Linq;

#region 객체 리스트 특정 객체 속성 값의 집합 구하기 - GetDistinctList(sourceList, propertyNameArray)

/// <summary>
/// 객체 리스트 특정 객체 속성 값의 집합 구하기
/// </summary>
/// <param name="sourceList">소스 리스트</param>
/// <param name="propertyNameArray">속성명 배열</param>
/// <returns>객체 리스트 특정 객체 속성 값의 집합</returns>
public List<object> GetDistinctList(List<object> sourceList, string[] propertyNameArray)
{
    if(sourceList == null || sourceList.Count == 0)
    {
        return null;
    }

    var result = sourceList.AsEnumerable().GroupBy(item => new DistinctTuple<object>(from propertyName in propertyNameArray select item.GetType().GetProperty(propertyName).GetValue(item)));

    int propertyNameCount = propertyNameArray.Length;

    PropertyDescriptorCollection pdc = TypeDescriptor.GetProperties(sourceList[0]);

    DynamicClass dynamicClass = new DynamicClass(); // '동적 클래스 사용하기' 참조

    for(int i = 0; i < propertyNameCount; i++)
    {
        dynamicClass.AddProperty(propertyNameArray[i], pdc[propertyNameArray[i]].PropertyType);
    }

    dynamicClass.CreateType();

    List<object> targetList = new List<object>();

    foreach(var group in result)
    {
        dynamicClass.CreateInstance();

        for(int i = 0; i < propertyNameCount; i++)
        {
            dynamicClass.SetValue(i, group.Key.ValueArray[i]);
        }

        targetList.Add(dynamicClass.Instance);
    }

    return targetList;
}

#endregion



/// <summary>
/// 중복 제거 튜플
/// </summary>
/// <typeparam name="T">타입</typeparam>
public class DistinctTuple<T> : IEquatable<DistinctTuple<T>>
{
    //////////////////////////////////////////////////////////////////////////////////////////////////// Field
    ////////////////////////////////////////////////////////////////////////////////////////// Public

    #region Field

    /// <summary>
    /// 값 배열
    /// </summary>
    public readonly T[] ValueArray;

    #endregion

    //////////////////////////////////////////////////////////////////////////////////////////////////// Constructor
    ////////////////////////////////////////////////////////////////////////////////////////// Public

    #region 생성자 - DistinctTuple(enumerable)

    /// <summary>
    /// 생성자
    /// </summary>
    /// <param name="enumerable">열거 가능형</param>
    public DistinctTuple(IEnumerable<T> enumerable)
    {
        ValueArray = enumerable.ToArray();
    }

    #endregion

    //////////////////////////////////////////////////////////////////////////////////////////////////// Method
    ////////////////////////////////////////////////////////////////////////////////////////// Public

    #region 동등 여부 조사하기 - Equals(sourceTuple)

    /// <summary>
    /// 동등 여부 조사하기
    /// </summary>
    /// <param name="sourceTuple">소스 Tuple</param>
    /// <returns>동등 여부</returns>
    public bool Equals(DistinctTuple<T> sourceTuple)
    {
        if(ReferenceEquals(this, sourceTuple))
        {
            return true;
        }

        if(sourceTuple == null)
        {
            return false;
        }

        int length = ValueArray.Length;

        if(length != sourceTuple.ValueArray.Length)
        {
            return false;
        }

        for(int i = 0; i < length; i++)
        {
            if(!Equals(ValueArray[i], sourceTuple.ValueArray[i]))
            {
                return false;
            }
        }

        return true;
    }

    #endregion

    #region 동등 여부 조사하기 - Equals(sourceObject)

    /// <summary>
    /// 동등 여부 조사하기
    /// </summary>
    /// <param name="sourceObject">소스 객체</param>
    /// <returns>동등 여부</returns>
    public override bool Equals(object sourceObject)
    {
        if(ReferenceEquals(this, sourceObject))
        {
            return false;
        }

        if(sourceObject == null)
        {
            return false;
        }

        return Equals(sourceObject as DistinctTuple<T>);
    }

    #endregion

    #region 해시 코드 구하기 - GetHashCode()

    /// <summary>
    /// 해시 코드 구하기
    /// </summary>
    /// <returns>해시 코드</returns>
    public override int GetHashCode()
    {
        int hashCode = 17;

        foreach(var value in ValueArray)
        {
            hashCode = hashCode * 37 + (!ReferenceEquals(value, null) ? value.GetHashCode() : 0);
        }

        return hashCode;
    }

    #endregion
}

100

101

102

103

104

105

106

107

108

109

110

111

112

113

114

115

116

117

118

119

120

121

122

123

124

125

126

127

128

129

130

131

132

133

134

135

136

137

138

139

140

141

142

143

144

145

146

147

148

149

150

151

152

153

154

155

156

157

158

159

160

161

162

163

164

165

166

167

168

169

170

171

172

173

174

175

176

177

178

using System;

using System.Collections.Generic;

using System.ComponentModel;

using System.Linq;

#region 객체 리스트 특정 객체 속성 값의 집합 구하기 - GetDistinctList(sourceList, propertyNameArray)

/// <summary>

/// 객체 리스트 특정 객체 속성 값의 집합 구하기

/// </summary>

/// <param name="sourceList">소스 리스트</param>

/// <param name="propertyNameArray">속성명 배열</param>

/// <returns>객체 리스트 특정 객체 속성 값의 집합</returns>

public List<object> GetDistinctList(List<object> sourceList, string[] propertyNameArray)

{

if(sourceList == null || sourceList.Count == 0)

{

return null;

}

var result = sourceList.AsEnumerable().GroupBy(item => new DistinctTuple<object>(from propertyName in propertyNameArray select item.GetType().GetProperty(propertyName).GetValue(item)));

int propertyNameCount = propertyNameArray.Length;

PropertyDescriptorCollection pdc = TypeDescriptor.GetProperties(sourceList[0]);

DynamicClass dynamicClass = new DynamicClass(); // '동적 클래스 사용하기' 참조

for(int i = 0; i < propertyNameCount; i++)

{

dynamicClass.AddProperty(propertyNameArray[i], pdc[propertyNameArray[i]].PropertyType);

}

dynamicClass.CreateType();

List<object> targetList = new List<object>();

foreach(var group in result)

{

dynamicClass.CreateInstance();

for(int i = 0; i < propertyNameCount; i++)

{

dynamicClass.SetValue(i, group.Key.ValueArray[i]);

}

targetList.Add(dynamicClass.Instance);

}

return targetList;

}

#endregion

/// <summary>

/// 중복 제거 튜플

/// </summary>

/// <typeparam name="T">타입</typeparam>

public class DistinctTuple<T> : IEquatable<DistinctTuple<T>>

{

//////////////////////////////////////////////////////////////////////////////////////////////////// Field

////////////////////////////////////////////////////////////////////////////////////////// Public

#region Field

/// <summary>

/// 값 배열

/// </summary>

public readonly T[] ValueArray;

#endregion

//////////////////////////////////////////////////////////////////////////////////////////////////// Constructor

////////////////////////////////////////////////////////////////////////////////////////// Public

#region 생성자 - DistinctTuple(enumerable)

/// <summary>

/// 생성자

/// </summary>

/// <param name="enumerable">열거 가능형</param>

public DistinctTuple(IEnumerable<T> enumerable)

{

ValueArray = enumerable.ToArray();

}

#endregion

//////////////////////////////////////////////////////////////////////////////////////////////////// Method

////////////////////////////////////////////////////////////////////////////////////////// Public

#region 동등 여부 조사하기 - Equals(sourceTuple)

/// <summary>

/// 동등 여부 조사하기

/// </summary>

/// <param name="sourceTuple">소스 Tuple</param>

/// <returns>동등 여부</returns>

public bool Equals(DistinctTuple<T> sourceTuple)

{

if(ReferenceEquals(this, sourceTuple))

{

return true;

}

if(sourceTuple == null)

{

return false;

}

int length = ValueArray.Length;

if(length != sourceTuple.ValueArray.Length)

{

return false;

}

for(int i = 0; i < length; i++)

{

if(!Equals(ValueArray[i], sourceTuple.ValueArray[i]))

{

return false;

}

return true;

}

#endregion

#region 동등 여부 조사하기 - Equals(sourceObject)

/// <summary>

/// 동등 여부 조사하기

/// </summary>

/// <param name="sourceObject">소스 객체</param>

/// <returns>동등 여부</returns>

public override bool Equals(object sourceObject)

{

if(ReferenceEquals(this, sourceObject))

{

return false;

}

if(sourceObject == null)

{

return false;

}

return Equals(sourceObject as DistinctTuple<T>);

}

#endregion

#region 해시 코드 구하기 - GetHashCode()

/// <summary>

/// 해시 코드 구하기

/// </summary>

/// <returns>해시 코드</returns>

public override int GetHashCode()

{

int hashCode = 17;

foreach(var value in ValueArray)

{

hashCode = hashCode * 37 + (!ReferenceEquals(value, null) ? value.GetHashCode() : 0);

}

return hashCode;

}

#endregion

}