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C#实现DataTable转换成IList的方法

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这篇文章主要介绍了C#实现DataTable转换成IList的方法,涉及C#针对DataTable操作的相关技巧,需要的朋友可以参考下

本文实例讲述了C#实现DataTable转换成IList的方法。分享给大家供大家参考，具体如下：

在用C#作开发的时候经常要把DataTable转换成IList；操作DataTable比较麻烦，把DataTable转换成IList，以对象实体作为IList的元素，操作起来就非常方便。

注意：实体的属性必须和数据库中的字段必须一一对应，或者数据库字段名.ToLower().Contains(实体属性名.ToLower())

数据类型暂时至支持int、string、DateTime、float、double

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using System;
using System.Collections;
using System.Collections.Generic;
using System.Data;
using System.Reflection;
namespace TBToListTest
{
  public class TBToList<T> where T : new()
  {
    /// <summary>
    /// 获取列名集合
    /// </summary>
    private IList<string> GetColumnNames(DataColumnCollection dcc)
    {
      IList<string> list = new List<string>();
      foreach (DataColumn dc in dcc)
      {
        list.Add(dc.ColumnName);
      }
      return list;
    }
    /// <summary>
    ///属性名称和类型名的键值对集合
    /// </summary>
    private Hashtable GetColumnType(DataColumnCollection dcc)
    {
      if (dcc == null || dcc.Count == 0)
      {
        return null;
      }
      IList<string> colNameList = GetColumnNames(dcc);
      Type t = typeof(T);
      PropertyInfo[] properties = t.GetProperties();
      Hashtable hashtable = new Hashtable();
      int i = 0;
      foreach (PropertyInfo p in properties)
      {
        foreach (string col in colNameList)
        {
          if (col.ToLower().Contains(p.Name.ToLower()))
          {
            hashtable.Add(col, p.PropertyType.ToString() + i++);
          }
        }
      }
      return hashtable;
    }
    /// <summary>
    /// DataTable转换成IList
    /// </summary>
    /// <param name="dt"></param>
    /// <returns></returns>
    public IList<T> ToList(DataTable dt)
    {
      if (dt == null || dt.Rows.Count == 0)
      {
        return null;
      }
      PropertyInfo[] properties = typeof(T).GetProperties();//获取实体类型的属性集合
      Hashtable hh = GetColumnType(dt.Columns);//属性名称和类型名的键值对集合
      IList<string> colNames = GetColumnNames(hh);//按照属性顺序的列名集合
      List<T> list = new List<T>();
      T model = default(T);
      foreach (DataRow dr in dt.Rows)
      {
        model = new T();//创建实体
        int i = 0;
        foreach (PropertyInfo p in properties)
        {
          if (p.PropertyType == typeof(string))
          {
            p.SetValue(model, dr[colNames[i++]], null);
          }
          else if (p.PropertyType == typeof(int))
          {
            p.SetValue(model, int.Parse(dr[colNames[i++]].ToString()), null);
          }
          else if (p.PropertyType == typeof(DateTime))
          {
            p.SetValue(model, DateTime.Parse(dr[colNames[i++]].ToString()), null);
          }
          else if (p.PropertyType == typeof(float))
          {
            p.SetValue(model, float.Parse(dr[colNames[i++]].ToString()), null);
          }
          else if (p.PropertyType == typeof(double))
          {
            p.SetValue(model, double.Parse(dr[colNames[i++]].ToString()), null);
          }
        }
        list.Add(model);
      }
      return list;
    }
    /// <summary>
    /// 按照属性顺序的列名集合
    /// </summary>
    private IList<string> GetColumnNames(Hashtable hh)
    {
      PropertyInfo[] properties = typeof(T).GetProperties();//获取实体类型的属性集合
      IList<string> ilist = new List<string>();
      int i = 0;
      foreach (PropertyInfo p in properties)
      {
        ilist.Add(GetKey(p.PropertyType.ToString() + i++, hh));
      }
      return ilist;
    }
    /// <summary>
    /// 根据Value查找Key
    /// </summary>
    private string GetKey(string val, Hashtable tb)
    {
      foreach (DictionaryEntry de in tb)
      {
        if (de.Value.ToString() == val)
        {
          return de.Key.ToString();
        }
      }
      return null;
    }
  }
}
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namespace TBToListTest
{
  //实体
  public class Person
  {
    public int ID
    {
      set;
      get;
    }
    public string Name
    {
      set;
      get;
    }
    public string Age
    {
      set;
      get;
    }
    public string Lover
    {
      set;
      get;
    }
  }
}
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using System;
using System.Data;
namespace TBToListTest
{
  class Program
  {
    static void Main(string[] args)
    {
      TBToList<Person> tol = new TBToList<Person>();
      Console.WriteLine();
      DataTable dt = GetTable();
      tol.ToList(dt);
      Console.Read();
    }
    public static DataTable GetTable()
    {
      DataTable dt = new DataTable();
      dt.Columns.Add("ID");
      dt.Columns.Add("Age");
      dt.Columns.Add("Lover");
      dt.Columns.Add("Name");
      DataRow dr = dt.NewRow();
      dr["ID"] = 1;
      dr["Age"] = "Age1";
      dr["Lover"] = "Lover1";
      dr["Name"] = "Name1";
      dt.Rows.Add(dr);
      DataRow dr1 = dt.NewRow();
      dr1["ID"] = 2;
      dr1["Age"] = "Age2";
      dr1["Lover"] = "Lover2";
      dr1["Name"] = "Name2";
      dt.Rows.Add(dr1);
      return dt;
    }
  }
}

希望本文所述对大家C#程序设计有所帮助。