C#中DataTable的创建与遍历

C#中DataTable的创建与遍历

1、创建DataTable对象

/// 

/// 创建DataTable对象
/// 
public static DataTable CreateDataTable()
{
    //创建DataTable
    DataTable dt = new DataTable("NewDt");
            
    //创建自增长的ID列
    DataColumn dc = dt.Columns.Add("ID", Type.GetType("System.Int32"));
    dc.AutoIncrement = true;   //自动增加
    dc.AutoIncrementSeed = 1;  //起始为1
    dc.AutoIncrementStep = 1;  //步长为1
    dc.AllowDBNull = false;    //非空

    //创建其它列表
    dt.Columns.Add(new DataColumn("Name", Type.GetType("System.String")));
    dt.Columns.Add(new DataColumn("Age", Type.GetType("System.Int32")));
    dt.Columns.Add(new DataColumn("Score", Type.GetType("System.Decimal")));
    dt.Columns.Add(new DataColumn("CreateTime", Type.GetType("System.DateTime")));

    //创建数据
    DataRow dr = dt.NewRow();
    dr["Name"] = "张三";
    dr["Age"] = 28;
    dr["Score"] = 85.5;
    dr["CreateTime"] = DateTime.Now;
    dt.Rows.Add(dr);

    dr = dt.NewRow();
    dr["Name"] = "李四";
    dr["Age"] = 24;
    dr["Score"] = 72;
    dr["CreateTime"] = DateTime.Now;
    dt.Rows.Add(dr);

    dr = dt.NewRow();
    dr["Name"] = "王五";
    dr["Age"] = 36;
    dr["Score"] = 63.5;
    dr["CreateTime"] = DateTime.Now;
    dt.Rows.Add(dr);

    return dt;
}

2、遍历DataTable对象

/// 

/// 遍历DataTable对象,转换成List对象
/// 
public static List TraverseDataTable(DataTable dt)
{
    List userList = new List();

    //判断DataTable是否为空
    if (dt == null || dt.Rows.Count == 0)
    {
        return null;
    }

    //遍历DataTable对象,转换成List
    foreach (DataRow row in dt.Rows)
    {
        UserInfo user = new UserInfo();

        if (dt.Columns.Contains("ID") && !Convert.IsDBNull(row["ID"]))
            user.ID = Convert.ToInt32(row["ID"]);

        if (dt.Columns.Contains("Name") && !Convert.IsDBNull(row["Name"]))
            user.Name = Convert.ToString(row["Name"]);

        if (dt.Columns.Contains("Age") && !Convert.IsDBNull(row["Age"]))
            user.Age = Convert.ToInt32(row["Age"]);

        if (dt.Columns.Contains("Score") && !Convert.IsDBNull(row["Score"]))
            user.Score = Convert.ToDouble(row["Score"]);

        if (dt.Columns.Contains("CreateTime") && !Convert.IsDBNull(row["CreateTime"]))
            user.CreateTime = Convert.ToDateTime(row["CreateTime"]);

        userList.Add(user);
    }

    return userList;
}

其它代码：

/// 

/// 用户信息类
/// 
public class UserInfo
{
    /// 

    /// 编号
    /// 
    public int ID { get; set; }

    /// 

    /// 名称
    /// 
    public string Name { get; set; }

    /// 

    /// 年龄
    /// 
    public int Age { get; set; }

    /// 

    /// 成绩
    /// 
    public double Score { get; set; }

    /// 

    /// 创建时间
    /// 
    public DateTime CreateTime { get; set; }
}