Question

尝试从LINQ查询中检索某些内容时遇到问题。我有一个prodList存储所有产品记录。另一个列表是distSPUItemList，它存储记录分布式项目记录。这是代码：

//Get list of products based on category and bind data to grid view
prodList = prodPackBLL.getAllProductByCategory(category);
gv.DataSource = prodList;
gv.DataBind();

//Mark checkbox checked for products included in standard packing list
var SPUItemList = new List<DistributionStandardPackingUnitItems>();
SPUItemList = packBLL.getAllSPUItemByDistributionID(distributionID);

//LINQ query to compare lists of objects finding ProductPacking 
//objects whose name property are equal to the items in SPUItemList
var available = from a in prodList
                // perform an inner-join between prodList and SPUItemList only
                // (x => x.name == a.name) compares b.name to a.name, this is 
                // specifically what enforces that names match
                from b in SPUItemList.Where(x => x.name == a.name)
                // after inner joining is done, only select objects from prodList
                select a;

//Iterate the gridview rows
GridView gvForCheckBox = (GridView)e.Item.FindControl("gvProduct") as GridView;
foreach (GridViewRow gr in gvForCheckBox.Rows)
{
    if (available.Where(x => x.name == gr.Cells[1].Text).Any())
    {
        CheckBox cb = (CheckBox)gr.Cells[0].FindControl("cbCheckRow");
        cb.Checked = true;
        TextBox tb = (TextBox)gr.Cells[3].FindControl("tbQuantity");
        //From here retrieve name and pass it to data access layer to perform SQL
        //Display unitQuantity if name match. If not default text set to 0
    }
}

所以基本上我要做的是from if (available.Where(x => x.name == gr.Cells[1].Text).Any()){}，如果名称匹配，我选中复选框。
同时，我需要根据数据库中的unitQuantity来打包productName。但我不知道如何从LINQ查询中检索名称。

对不起我的不良解释并提前致谢。

编辑部分：

 string name = gr.Cells[1].Text;
                            int productQuantity = packBLL.getProductQuantityByName(name);
                            TextBox tb = (TextBox)gr.Cells[3].FindControl("tbQuantity");
                            tb.Text = productQuantity.ToString();

适用于此。首先，我通过指定列获取名称，然后执行其他一些Sql语句

Answer 1

如果我没有误解你的实际操作，可以尝试将foreach循环内部更改为：

var rowData = available.Where(x => x.name == gr.Cells[1].Text).FirstOrDefault();
//if rowData == null, means no matching data in `available` variable
if (rowData != null)
{
    CheckBox cb = (CheckBox)gr.Cells[0].FindControl("cbCheckRow");
    cb.Checked = true;
    TextBox tb = (TextBox)gr.Cells[3].FindControl("tbQuantity");
    //example on how to get current name
    var name = rowData.name;
}

从LINQ查询中检索变量

1 个答案: