datalist在多个单元格上更改背景颜色

Question

我想更改每个datalist单元格的背景颜色。但我只能改变一种颜色......就像这样...

我想在selectedIndex Changed ...

上实现这个逻辑

protected void DataList1_SelectedIndexChanged(object sender, EventArgs e)
{
    foreach (DataListItem dli in DataList1.Items)
    {
        //if cell is not red make it red
        DataList1.SelectedItem.BackColor = Color.Red;

        //else cell is red .. make it blue(unselect)
    }        
}

如何实现切换功能？

Answer 1

创建两个静态辅助字段，用于定义默认颜色和所选颜色，并使用ternary operator切换它们：

private static Color DefaultBackColor = Color.Blue;
private static Color SelectedBackColor = Color.Red;

protected void DataList1_SelectedIndexChanged(object sender, EventArgs e)
{
    foreach (DataListItem dli in DataList1.Items)
    {
        dli.BackColor =
            dli == DataList1.SelectedItem
            ? SelectedBackColor;
            : DefaultBackColor;
        }
    }
}