C# 将按钮列添加到datagrid视图会导致问题
我有一个datagridview绑定,其中的数据来自运行良好的数据库。当表单加载时,它将加载数据。根据客户的要求,我使用以下代码向datagrid视图添加了新的按钮列C# 将按钮列添加到datagrid视图会导致问题,c#,winforms,button,datagridview,datagridviewcolumn,C#,Winforms,Button,Datagridview,Datagridviewcolumn,我有一个datagridview绑定,其中的数据来自运行良好的数据库。当表单加载时,它将加载数据。根据客户的要求,我使用以下代码向datagrid视图添加了新的按钮列 private void form1_load { var productsbycount = abc.products.GroupBy(x => x.product_Id).Select(a => new { productid = a.Key,
private void form1_load
{
var productsbycount = abc.products.GroupBy(x => x.product_Id).Select(a => new
{
productid = a.Key,
prouctnam = a.FirstOrDefault().product_Name,
productimage = a.FirstOrDefault().product_Image,
productdescr = a.FirstOrDefault().product_Description,
stockavailable = a.LongCount(),
productprice = a.FirstOrDefault().product_Price
});
productbindingsource.DataSource = productsbycount;
productgridview.DataSource = productbindingsource;
DataGridViewButtonColumn buttoncolumn = new DataGridViewButtonColumn();
productgridview.Columns.Add(buttoncolumn);
buttoncolumn.Text = "Buy";
buttoncolumn.HeaderText = "Buy";
buttoncolumn.UseColumnTextForButtonValue = true;
buttoncolumn.Name = "btnbuy";
productgridview.Columns[0].Visible = false;
}
当模板加载时,其工作状态良好
但我检查的条件是,如果我们在列表视图中选择任何一项,那么datagrid视图将根据所选项进行排序。。。为此,我已经这样做了
if (lstviewcategories.SelectedItems[0].Value.ToString() == "All")
{
var productsbycount = abc.products.GroupBy(x => x.product_Id).Select(a => new
{
productid = a.Key,
prouctnam = a.FirstOrDefault().product_Name,
productimage = a.FirstOrDefault().product_Image,
productdescr = a.FirstOrDefault().product_Description,
stockavailable = a.LongCount(),
productprice = a.FirstOrDefault().product_Price
});
productbindingsource.DataSource = productsbycount;
productgridview.DataSource = productbindingsource;
DataGridViewButtonColumn buttoncolumn = new DataGridViewButtonColumn();
productgridview.Columns.Add(buttoncolumn);
buttoncolumn.Text = "Buy";
buttoncolumn.HeaderText = "Buy";
buttoncolumn.UseColumnTextForButtonValue = true;
buttoncolumn.Name = "btnbuy";
productgridview.Columns[0].Visible = false;
}
- 如果单击listview第一项(“全部”),则datagrid视图 工作很好
- 如果我再次单击listview的第一项(“全部”),则按钮列为 出现两次
- 如果我再次单击listview的第一项(“全部”),则按钮列为 出现三次
if (lstviewcategories.SelectedItems[0].Value.ToString() == "All")
{
}
实际的按钮列消失了。请任何人帮忙
修改代码:
第一个条件:if(lstviewcategories.SelectedItems[0].Text.ToString()==CategoryType.Type2)
{
var productsbycount = abc.products.GroupBy(x => x.product_Id).Where(a => a.FirstOrDefault().product_Price > 0 && a.FirstOrDefault().product_Price <= 1000)
.Select(a => new
{
productid = a.Key,
prouctnam = a.FirstOrDefault().product_Name,
productimage = a.FirstOrDefault().product_Image,
productdescr = a.FirstOrDefault().product_Description,
stockavailable = a.LongCount(),
productprice = a.FirstOrDefault().product_Price
});
productbindingsource.ResetBindings(false);
/*productbindingsource.DataSource = productsbycount;
productgridview.DataSource = productbindingsource;
DataGridViewButtonColumn buttoncolumn = new DataGridViewButtonColumn();
productgridview.Columns.Add(buttoncolumn);
buttoncolumn.Text = "Buy";
buttoncolumn.HeaderText = "Buy";
buttoncolumn.UseColumnTextForButtonValue = true;
buttoncolumn.Name = "btnbuy";
productgridview.Columns[0].Visible = false;*/
}
var productsbycount=abc.products.GroupBy(x=>x.product\u Id)。其中(a=>a.FirstOrDefault().product\u Price>0和&a.FirstOrDefault().product\u Price新
{
productid=a.键,
prouctnam=a.FirstOrDefault().product\U名称,
productimage=a.FirstOrDefault().product\U图像,
productdescr=a.FirstOrDefault()。产品描述,
stockavailable=a.LongCount(),
productprice=a.FirstOrDefault().产品价格
});
productbindingsource.ResetBindings(false);
/*productbindingsource.DataSource=productsbycount;
productgridview.DataSource=productbindingsource;
DataGridViewButtonColumn buttoncolumn=新DataGridViewButtonColumn();
productgridview.Columns.Add(buttoncolumn);
buttoncolumn.Text=“购买”;
buttoncolumn.HeaderText=“购买”;
buttoncolumn.UseColumnTextForButtonValue=true;
buttoncolumn.Name=“btnbuy”;
productgridview.Columns[0]。Visible=false*/
}
第二个条件:
if (lstviewcategories.SelectedItems[0].Text.ToString() == CategoryType.Type3)
{
var productsbycount = abc.products.GroupBy(x => x.product_Id).Where(a => a.FirstOrDefault().product_Price > 500 && a.FirstOrDefault().product_Price <= 1000)
.Select(a => new
{
productid = a.Key,
prouctnam = a.FirstOrDefault().product_Name,
productimage = a.FirstOrDefault().product_Image,
productdescr = a.FirstOrDefault().product_Description,
stockavailable = a.LongCount(),
productprice = a.FirstOrDefault().product_Price
});
productbindingsource.ResetBindings(false);
/* productbindingsource.DataSource = productsbycount;
productgridview.DataSource = productbindingsource;
DataGridViewButtonColumn buttoncolumn = new DataGridViewButtonColumn();
productgridview.Columns.Add(buttoncolumn);
buttoncolumn.Text = "Buy";
buttoncolumn.HeaderText = "Buy";
buttoncolumn.UseColumnTextForButtonValue = true;
buttoncolumn.Name = "btnbuy";
productgridview.Columns[0].Visible = false;*/
}
if(lstviewcategories.SelectedItems[0].Text.ToString()==CategoryType.Type3)
{
var productsbycount=abc.products.GroupBy(x=>x.product\u Id)。其中(a=>a.FirstOrDefault()。product\u Price>500&&a.FirstOrDefault()。product\u Price新建
{
productid=a.键,
prouctnam=a.FirstOrDefault().product\U名称,
productimage=a.FirstOrDefault().product\U图像,
productdescr=a.FirstOrDefault()。产品描述,
stockavailable=a.LongCount(),
productprice=a.FirstOrDefault().产品价格
});
productbindingsource.ResetBindings(false);
/*productbindingsource.DataSource=productsbycount;
productgridview.DataSource=productbindingsource;
DataGridViewButtonColumn buttoncolumn=新DataGridViewButtonColumn();
productgridview.Columns.Add(buttoncolumn);
buttoncolumn.Text=“购买”;
buttoncolumn.HeaderText=“购买”;
buttoncolumn.UseColumnTextForButtonValue=true;
buttoncolumn.Name=“btnbuy”;
productgridview.Columns[0]。Visible=false*/
}
这两种情况都不起作用。首先,我强烈建议大家阅读干燥原理。为了回答您的问题,我建议您使用
BindingSource
的刷新方法,这样您就可以在不更改数据结构的情况下刷新datagridview中的数据。您应该只在加载时执行以下所有操作一次,然后在其他任何地方刷新数据,除非您确实想要更改数据类型,例如数据来自不同的源
productbindingsource.DataSource = productsbycount;
productgridview.DataSource = productbindingsource;
DataGridViewButtonColumn buttoncolumn = new DataGridViewButtonColumn();
productgridview.Columns.Add(buttoncolumn);
buttoncolumn.Text = "Buy";
buttoncolumn.HeaderText = "Buy";
buttoncolumn.UseColumnTextForButtonValue = true;
buttoncolumn.Name = "btnbuy";
productgridview.Columns[0].Visible = false;
不要在下面的代码块中再次执行这些操作,只需调用productbindingsource.ResetBindings(false)
更新:另外,不要在这个代码块中定义var productsbycount,而是在最顶端将其作为一个类变量,以便您可以访问所有方法,这样当您刷新数据时,您将覆盖以前的var productsbycount,它将工作得非常好
UPDATE2:'ResetBindings()可以在更改数据后的任何时候使用,但正如我已经说过的,您需要一个类级变量(也就是将var productsbycount放在类的顶部),在本例中,它将紧跟其后
productprice = a.FirstOrDefault().product_Price
});
更新3:我重复一遍,我们在这里提供帮助和建议,不是为您编写整个代码,而是因为我感觉很好=)我也重复一遍,这里似乎存在大量重复,随着代码库的增长,这可能会给您带来巨大的痛苦
namespace Test
{
public partial class Form2 : Form
{
BindingSource productbindingsource;
var productsbycount;
public Form2()
{
InitializeComponent();
Load += new EventHandler(Form2_Load);
}
void Form2_Load(object sender, EventArgs e)
{
productsbycount = abc.products.GroupBy(x => x.product_Id).Select(a => new
{
productid = a.Key,
prouctnam = a.FirstOrDefault().product_Name,
productimage = a.FirstOrDefault().product_Image,
productdescr = a.FirstOrDefault().product_Description,
stockavailable = a.LongCount(),
productprice = a.FirstOrDefault().product_Price
});
productbindingsource.DataSource = productsbycount;
productgridview.DataSource = productbindingsource;
DataGridViewButtonColumn buttoncolumn = new DataGridViewButtonColumn();
productgridview.Columns.Add(buttoncolumn);
buttoncolumn.Text = "Buy";
buttoncolumn.HeaderText = "Buy";
buttoncolumn.UseColumnTextForButtonValue = true;
buttoncolumn.Name = "btnbuy";
productgridview.Columns[0].Visible = false;
}
private void methodNameHere()
{
productsbycount = abc.products.GroupBy(x => x.product_Id).Where(a => a.FirstOrDefault().product_Price > 0 && a.FirstOrDefault().product_Price <= 1000)
.Select(a => new
{
productid = a.Key,
prouctnam = a.FirstOrDefault().product_Name,
productimage = a.FirstOrDefault().product_Image,
productdescr = a.FirstOrDefault().product_Description,
stockavailable = a.LongCount(),
productprice = a.FirstOrDefault().product_Price
});
productbindingsource.ResetBindings(false);
}
}
}
名称空间测试
{
公共部分类表单2:表单
{
BindingSource产品BindingSource;
var productsbycount;
公共表格2()
{
初始化组件();
荷载+=n
namespace Test
{
public partial class Form2 : Form
{
BindingSource productbindingsource;
var productsbycount;
public Form2()
{
InitializeComponent();
Load += new EventHandler(Form2_Load);
}
void Form2_Load(object sender, EventArgs e)
{
productsbycount = abc.products.GroupBy(x => x.product_Id).Select(a => new
{
productid = a.Key,
prouctnam = a.FirstOrDefault().product_Name,
productimage = a.FirstOrDefault().product_Image,
productdescr = a.FirstOrDefault().product_Description,
stockavailable = a.LongCount(),
productprice = a.FirstOrDefault().product_Price
});
productbindingsource.DataSource = productsbycount;
productgridview.DataSource = productbindingsource;
DataGridViewButtonColumn buttoncolumn = new DataGridViewButtonColumn();
productgridview.Columns.Add(buttoncolumn);
buttoncolumn.Text = "Buy";
buttoncolumn.HeaderText = "Buy";
buttoncolumn.UseColumnTextForButtonValue = true;
buttoncolumn.Name = "btnbuy";
productgridview.Columns[0].Visible = false;
}
private void methodNameHere()
{
productsbycount = abc.products.GroupBy(x => x.product_Id).Where(a => a.FirstOrDefault().product_Price > 0 && a.FirstOrDefault().product_Price <= 1000)
.Select(a => new
{
productid = a.Key,
prouctnam = a.FirstOrDefault().product_Name,
productimage = a.FirstOrDefault().product_Image,
productdescr = a.FirstOrDefault().product_Description,
stockavailable = a.LongCount(),
productprice = a.FirstOrDefault().product_Price
});
productbindingsource.ResetBindings(false);
}
}
}
if (lstviewcategories.SelectedItems[0].Text.ToString() == CategoryType.Type2)
productgridview.datasource = productsbycount.Where(a => a.FirstOrDefault().product_Price > 0 && a.FirstOrDefault().product_Price <= 1000)