根据数据更改gridview中行的颜色

Question

我在ASP.Net中有一个Gridview - C＃。我有一个名为Assignment或Exam的专栏。在那一栏中，我有作业或考试的名称，例如："Exam 1"，"Assignment 5"我希望作为作业的每一行都应该是红色并且考试是蓝色的。

在SQL Server或我的代码中，最好的方法是什么？如果是这样，什么是正确的代码？

Answer 1

您可以通过分别为每一行设置BackColor属性来设置Gridview中行的背景颜色。要根据行中的数据执行此操作，您需要检查绑定的行，您可以在RowDataBound事件中执行此操作。这里是基本Gridview的快速标记，我们连接到服务器端事件：

<asp:GridView runat="server" AutoGenerateColumns="False" OnRowDataBound="TestGridView_RowDataBound" ID="TestGridView">
    <Columns>
        <asp:BoundField DataField="Type" HeaderText="Assignment/Exam" />
        <asp:BoundField DataField="Name" HeaderText="Name" />
    </Columns>
</asp:GridView>

protected void Page_Load(object sender, EventArgs e)
{
    DataTable tests = new DataTable();
    tests.Columns.Add(new DataColumn("Type"));
    tests.Columns.Add(new DataColumn("Name"));
    tests.AcceptChanges();

    tests.Rows.Add(new []{"Assignment","StackOverflow Basics"});
    tests.Rows.Add(new[]{"Exam","Expert Markdown"});
    tests.Rows.Add(new[]{"Exam","Upvoting"});
    tests.Rows.Add(new[]{"Assignment","Rep Changes"});

    TestGridView.DataSource = tests;
    TestGridView.DataBind();
}

在事件的代码中，我们可以获取我们绑定的单个数据行并检查值，因此我们可以相应地设置BackColor：

protected void TestGridView_RowDataBound(object sender, GridViewRowEventArgs e)
{
    // Ignore the first row which is the header
    if (e.Row.RowType == DataControlRowType.DataRow)
    {
        // Get hold of the row and then the DataRow that it's being bound to
        GridViewRow row = e.Row;
        DataRow data = ((DataRowView)row.DataItem).Row;

        // Look at the value and set the colour accordingly
        switch (data.Field<string>("Type"))
        {
            case "Assignment":
                row.BackColor = System.Drawing.Color.FromName("Blue");
                break;
            case "Exam":
                row.BackColor = System.Drawing.Color.FromName("Red");
                break;
        }
    }
}

虽然您可能还想考虑将文本颜色设置为白色，因此它更容易阅读。

但是，您可能希望将来有更多的灵活性，例如如果您添加第三个名为“Lab”的评估类型为绿色，则需要更改/重新编译/重新测试/重新部署代码。相反，如果你从数据库中传递一个命名颜色然后在RowDataBound事件中使用它，你可以避免一些工作，例如：

protected void TestGridView_RowDataBound(object sender, GridViewRowEventArgs e)
{
    // Ignore the first row which is the header
    if (e.Row.RowType == DataControlRowType.DataRow)
    {
        // Get hold of the row and then the DataRow that it's being bound to
        GridViewRow row = e.Row;
        DataRow data = ((DataRowView)row.DataItem).Row;

        row.BackColor = System.Drawing.Color.FromName(data.Field<string>("BackColour");
        row.ForeColor = System.Drawing.Color.FromName(data.Field<string>("TextColour");
    }
}

Answer 2

首先在变量中找到行索引。在下面的代码中，我使用了index作为变量。

grdWithLocation.Rows[index].BackColor = Color.FromArgb(255, 238, 238, 238);

Answer 3

我在库存数据库中使用它。它检查它的日期，并将其与每个订单的数据库中的日期进行比较。然后根据它们坐了多长时间，用不同的颜色为每一行着色。它位于GridView的RowDataBound上

您应该能够修改代码以将日期更改为“考试/作业”

if (e.Row.RowType == DataControlRowType.DataRow)
{
    DateTime datToday = DateTime.Today();
    DateTime O1 = datToday.AddDays(0);
    DateTime O2 = datToday.AddDays(-1);
    DateTime O3 = datToday.AddDays(-4);

    string strMediaX = e.Row.Cells[2].Text;

    if (Information.IsDate(strMediaX))
    {
        DateTime MediaX = e.Row.Cells[2].Text;
        if (MediaX < O3)
        {
            e.Row.Cells[2].BackColor = Drawing.Color.OrangeRed;
            e.Row.Cells[2].ForeColor = Drawing.Color.White;
        }
        else if (MediaX < O2)
        {
            e.Row.Cells[2].BackColor = Drawing.Color.Orange;
            e.Row.Cells[2].ForeColor = Drawing.Color.White;
        }
        else if (MediaX < O1)
            e.Row.Cells[2].BackColor = Drawing.Color.Gold;
    }
    // checks the current stock of the item and if it is below 10 then it changes the colour to highlight that it needs to be ordered.
    if (e.Row.RowType == DataControlRowType.DataRow)
    {
        if ((Label)e.Row.Cells[9].FindControl("lblCurrentStock").Text < 11)
        {
            e.Row.Cells[9].BackColor = System.Drawing.Color.OrangeRed;
            e.Row.Cells[9].ForeColor = Drawing.Color.White;
            e.Row.Cells[9].Font.Bold = true;
        }
    }
}