窗口表单-使用gridview的数据绑定概念 [英] Window forms -- Data binding concepts using gridview
问题描述
我想要更好的解决方案来处理数据绑定中的关系..谢谢您
在组合框中输入部门名称时，在这里我必须在两个gridviews中显示两个表及其详细信息..
但是在这里添加关系并将数据集插入到gridview时是可以的，但是当我为网格视图插入dataMember时，它表明无法为数据集创建子字段.
dataGridView1.DataSource = dtviewMang;
dataGridView1.DataMember ="EmpDs.relEmpDetails";
在这里，我采用了简单的Sql Table-员工为Emp，部门为Dept，部门详细信息为deptDetails.
请解决问题，如果您得到了答案，请将其粘贴到此处.
谢谢..
i want better soloution to work with relations in data binding..thank u
Here i have to display the two tables in two gridviews and their details when i enter department name in combo box..
but here while adding relation and inserting dataset to gridview it''s ok but when i insert dataMember for grid view it show child field can''t be created for the dataset.
dataGridView1.DataSource = dtviewMang;
dataGridView1.DataMember = "EmpDs.relEmpDetails";
here i have taken simple Sql Table -- employee as Emp and Department as Dept and DepartmentDetails as deptDetails.
please solve the problem and if u got the answer please paste it down here..
Thank You..
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Data.Common;
using System.Collections;
using System.Data.SqlClient;
namespace WinForm1
{
public partial class SampleProg2 : Form
{
private String ConnectionString;
private DataViewManager dtviewMang;
private DataSet ds;
public SampleProg2()
{
InitializeComponent();
ConnectionString = "Data Source=ETG-75;Initial Catalog=test;Integrated Security=True";
SqlConnection con = new SqlConnection(ConnectionString);
ds = new DataSet("EmpDs");
SqlDataAdapter da1 = new SqlDataAdapter("select * from Emp", con);
da1.TableMappings.Add("Table", "Emp");
da1.Fill(ds);
SqlDataAdapter da2 = new SqlDataAdapter("select * from Dept", con);
da2.TableMappings.Add("Table", "Dept");
da2.Fill(ds);
SqlDataAdapter da3 = new SqlDataAdapter("select * from DeptDetails", con);
da3.TableMappings.Add("Table", "DeptDetail");
da3.Fill(ds);
//show created table names with in the dataset
string myMessage = "Table Mappings";
for (int i = 0; i < ds.Tables.Count; i++)
{
myMessage += i.ToString() + " " + ds.Tables[i].ToString()+" ";
}
//Establish the relation between Employee and dept tables
System.Data.DataRelation relEmpDetails;
// System.Data.DataColumn colemp1;
System.Data.DataColumn colDept1;
System.Data.DataColumn colemp1 = ds.Tables[0].Columns["Deptno"];
colDept1 = ds.Tables[1].Columns["Deptno"];
relEmpDetails = new System.Data.DataRelation("RelEmpDetails", colDept1, colemp1 );
ds.Relations.Add(relEmpDetails);
System.Data.DataRelation relDetpDetails;
System.Data.DataColumn colDept2;
System.Data.DataColumn colDeptdetail2;
colDept2 = ds.Tables[1].Columns["Deptno"];
colDeptdetail2 = ds.Tables[2].Columns["deptno"];
relDetpDetails = new System.Data.DataRelation("RelDeptDetails", colDept2, colDeptdetail2 );
ds.Relations.Add(relDetpDetails);
//show created relations with in the dataset
myMessage += "Relations Mappings:";
for (int i = 0; i < ds.Relations.Count; i++)
{
myMessage += i.ToString() + " " + ds.Relations[i].ToString() + " ";
}
textBox1.Text = myMessage;
// The DataViewManager returned by the DefaultViewManager
// property allows you to create custom settings for each
// DataTable in the DataSet.
dtviewMang = ds.DefaultViewManager;
错误出现在这里:
Error shows up here:
dataGridView1.DataSource = dtviewMang;
dataGridView1.DataMember = "EmpDs.relEmpDetails";//Error Here
dataGridView2.DataSource = dtviewMang;
dataGridView2.DataMember = "EmpDs.RelEmpDetails.RelDeptDetails"; // Error here
comboBox1.DataSource = dtviewMang;
comboBox1.DisplayMember = "EmpDs.DName";
comboBox1.ValueMember = "EmpDs.Dno"; //error here
textBox2.DataBindings.Add("Text", dtviewMang, "EmpDs.Loc");
textBox3.DataBindings.Add("Text", dtviewMang, "EmpDs.Comments");
}
private void button1_Click(object sender, EventArgs e)
{
if (this.BindingContext[dtviewMang, "EmpDs"].Position > 0)
{
this.BindingContext[dtviewMang, "EmpDs"].Position--;
}
}
private void button2_Click(object sender, EventArgs e)
{
CurrencyManager cm = (CurrencyManager)this.BindingContext[dtviewMang, "EmpDs"];
if (cm.Position < cm.Count - 1)
{
cm.Position++;
}
}
}
}
[edit]已添加代码块-OriginalGriff [/edit]
[edit]Code block added - OriginalGriff[/edit]
推荐答案
亲爱的同伴，
为什么不尝试linq.看一下这篇文章.我希望它能做到.这基本上与Entity Framework有关，但本文中存在对您问题的答案.
实体框架简介 [
Dear fellow,
Why not you try linq. Take a look at this article. I hope it will do. This basically relates to Entity framework but the answer to your question exists in this article.
Introduction to the Entity Framework[^]
//假设Fill_Details_By_Dept();是一个函数，返回一个
包含2个表的DataSet ds，
1 ds.tables [0]代表您的要求2列
2.ds.tables [1]代表您的要求1列
@假设您的网格有3列，并且网格名称为grd，然后
//suppose Fill_Details_By_Dept(); is a function return a
DataSet ds which contains 2 tables ,
1 ds.tables[0] conatins your req 2 columns
2.ds.tables[1] conatins your req 1 columns
@ suppose your grid hai 3 columns and your grid name is grd then
ds2 = Fill_Details_By_Dept();
for (int x = 0; x < ds.Tables[2].Rows.Count; x++)
{
grd.Rows[x].Cells[0].Value = ds.Tables[0].Rows[x].ItemArray[0];
grd.Rows[x].Cells[0].Value = ds.Tables[0].Rows[x].ItemArray[1];
grd.Rows[x].Cells[1].Value = ds.Tables[1].Rows[x].ItemArray[0];
因此您的网格中会填充您想要的结果....
enjoy:)
so your grid populate with the result you want....
enjoy :)
您似乎正在尝试将网格的数据源设置为关系.网格应该被赋予一个表或视图(或其他与数组无关的非System.Data东西，如数组，列表，IEnumerables等).尝试"EmpDs.Emp"，或直接将数据源设置为表:
You seem to be trying to set the data source of the grid to a relation. Grids expect to be given a table or view (or other non-System.Data things like arrays, lists, IEnumerables etc that aren''t relevant here). Try ''EmpDs.Emp'', or just set the DataSource to the table directly:
dataGridView1.DataSource = ds.Tables["Emp"];
这篇关于窗口表单-使用gridview的数据绑定概念的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
