应用小算法_.NET_编程开发_程序员俱乐部

最近在做一个WPF小项目，因为需要处理一些数据，迫不得已写了一个函数，算是一个小算法吧，在此写出以便温故知新，同时希望牛人不吝赐教，点出其中不足之处。

 

简化需求：

创建一个datatable表dt，dt表中的记录行数是变量m。创建datatable表dt1、dt2，dt1和dt2循环显示dt中的数据，添加一个计时器定时刷新dt1、dt2中的数据，且dt1和dt2每次只能显示n行。

 

1、声明变量

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private DispatcherTimer timer;
        DataTable dt = new DataTable();
        DataTable dt1 = new DataTable();
        DataTable dt2 = new DataTable();
        public static int currentRows = 0;//当前行
        public static int currentRows2 = 0;//中间变量

View Code

定时器：

timer = new DispatcherTimer();
            timer.Interval = new TimeSpan(0, 0, 5);
            timer.Tick += new EventHandler(timer_Tick);
            timer.Start();

View Code

 

2、添加控件，此处添加两个datagrid控件（用以显示dt1和dt2中的数据）

<DataGrid AutoGenerateColumns="False" Height="335" HorizontalAlignment="Left" Margin="220,12,0,0" Name="dataGrid1" VerticalAlignment="Top" Width="200" >
            <DataGrid.Columns >
                <DataGridTextColumn Header="id" Binding="{Binding Path=id}"></DataGridTextColumn>
                <DataGridTextColumn Header="name" Binding="{Binding Path=name}"></DataGridTextColumn>
            </DataGrid.Columns>
        </DataGrid>
        <DataGrid AutoGenerateColumns="False" Height="305" HorizontalAlignment="Left" Margin="463,31,0,0" Name="dataGrid2" VerticalAlignment="Top" Width="200" >
            <DataGrid.Columns >
                <DataGridTextColumn Header="id" Binding="{Binding Path=id}"></DataGridTextColumn>
                <DataGridTextColumn Header="name" Binding="{Binding Path=name}"></DataGridTextColumn>
            </DataGrid.Columns>
        </DataGrid>

View Code

 

3、创建datatable表dt，并且初始化dt1和dt2

private void Initialize(int num)
        {
            dt.Columns.Add(new DataColumn("id", typeof(int)));
            dt.Columns.Add(new DataColumn("name", typeof(string)));
            for (int i = 0; i < num; i++)
            {
                DataRow dr = dt.NewRow();
                dr["id"] = i;
                dr["name"] = "tom" + i.ToString();
                dt.Rows.Add(dr);
            }

            dt1.Columns.Add(new DataColumn("id", typeof(int)));
            dt1.Columns.Add(new DataColumn("name", typeof(string)));

            dt2.Columns.Add(new DataColumn("id", typeof(int)));
            dt2.Columns.Add(new DataColumn("name", typeof(string)));
        }

初始化时调用：

Initialize(11);

 

4、编写函数

public void Update(int num)
        {
            int rows = dt.Rows.Count;
            int num1 = 0;
            int num2 = 0;
            currentRows = currentRows2;

            for (int i = currentRows; i < (currentRows + num); i++)
            {
                num1++;
                currentRows2++;

                DataRow dr = dt1.NewRow();
                dr["id"] = Convert.ToInt32(dt.Rows[i][0].ToString());
                dr["name"] = dt.Rows[i][1].ToString();
                dt1.Rows.Add(dr);

                if (i == rows - 1)
                {
                    i = -1;
                    currentRows2 = 0;
                }

                if (num1 == num)
                {
                    break;
                }
            }

            currentRows = currentRows2;
            for (int i = currentRows; i < (currentRows + num); i++)
            {
                num2++;
                currentRows2++;

                DataRow dr = dt2.NewRow();
                dr["id"] = Convert.ToInt32(dt.Rows[i][0].ToString());
                dr["name"] = dt.Rows[i][1].ToString();
                dt2.Rows.Add(dr);

                if (i == rows - 1)
                {
                    i = -1;
                    currentRows2 = 0;
                }

                if (num2 == num)
                {
                    break;
                }
            }
        }

 

5、定时刷新dt1和dt2中的数据

void timer_Tick(object sender, EventArgs e)
        {
            dt1.Clear();
            dt2.Clear();
            Update(3);
            this.dataGrid1.ItemsSource = dt1.DefaultView;
            this.dataGrid2.ItemsSource = dt2.DefaultView;
        }