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  • C#webform LinQ

    LinQ的高级查询:

    模糊查

    con.Car.Where(r=>r.Name.Contains(cname)).ToList();


    以..开头

    con.car.Where(r => r.name.StartsWith(TextBox1.Text)).ToList();

    以..结尾

    con.car.Where(r => r.name.EndsWith(TextBox1.Text)).ToList();

    求最大值

    con.car.Max(r => r.price * r.oil).ToString();

    最小值

    con.car.Min(r => r.price).ToString();


    求和

    con.car.Sum(r => r.price).ToString();


    平均值

    con.car.Average(r => r.price).ToString();

    升序

    con.car.OrderBy(r => r.price).ToList();


    降序

    con.car.OrderByDescending(r => r.price).ToList();

    分页

    int pageNum = Convert.ToInt32(PageCount_Label.Text) + 1;

    Repeater1.DataSource = con.car.Skip((pageNum - 1) * PageCount).Take(PageCount);
    Repeater1.DataBind();
    PageCount_Label.Text = pageNum.ToString();

    组合查询

    List<car> list = con.car.ToList();

    if (TextBox2.Text != "")
    {
    List<car> list1 = con.car.Where(r => r.name.Contains(TextBox2.Text)).ToList();

    list = list.Intersect(list1).ToList();
    }
    if (TextBox3.Text != "")
    {
    List<car> list1 = con.car.Where(r => r.oil == Convert.ToDecimal(TextBox3.Text)).ToList();

    list = list.Intersect(list1).ToList();
    }
    if (TextBox4.Text != "")
    {
    List<car> list1 = con.car.Where(r => r.powers == Convert.ToInt32(TextBox4.Text)).ToList();

    list = list.Intersect(list1).ToList();
    }


    Repeater1.DataSource = list;
    Repeater1.DataBind();

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  • 原文地址:https://www.cnblogs.com/bloodPhoenix/p/5972007.html
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