dgJEARequests正如您从图像中看到的那样，我有以下方法可以在 gridview ( ) 中显示自定义的项目选择。用户将选择将参数发送到查询的项目whereStatement。但是当许多复选框（项目）被标记或选中时，加载所有数据需要一些时间，dgJEARequests比如 5000 条记录，或者更少。所以，我决定添加一个WaitProcessing（带有进度条的表单）。当我单击搜索按钮btnSearchSelection时，我收到此错误：
An exception of type 'System.InvalidOperationException' occurred in System.Windows.Forms.dll but was not handled in user code
附加信息：跨线程操作无效：控件“dgJEARequests”从创建它的线程以外的线程访问
private void ShowOnlyCustomSelection()
{
String whereStatement = "";
List<String> fieldList = new List<String>();
string getStatusName = "";
string _getStatusName = "";
//loop through all the checkboxes
for (int i = 0; i < count; i++)
{
if (_cbStatus[i].Checked)
{
//getStatusName should give all selected options like this: 'New', 'Started', 'Accepted', etc., then pass it to whereStatement
_getStatusName += ("'" + _cbStatus[i].Text + "'" + ",").TrimEnd();
}
}
//trims the last comma (,)
getStatusName = _getStatusName.TrimEnd(',');
//textBox1.Text = _getStatusName.TrimEnd(','); //--->>this is for testing
////////////
if (getStatusName == "" || getStatusName == null)
{
{
MessageBox.Show("You have not selected your filter(s)!", "Filter Result", MessageBoxButtons.OK, MessageBoxIcon.Exclamation);
}
}
else
{
//Build WHERE Statement
fieldList.Add("RequestStatus.StatusName IN (" + getStatusName + ")");
if (fieldList.Count > 0)
{
for (int x = 0; x < fieldList.Count; x++)
{
if (x == 0)
{
whereStatement = fieldList[x];
}
else
{
whereStatement = whereStatement + " AND " + fieldList[x];
}
}
//Seach for Requests
jeaRequests = itServices.getRequestsBySQLStatement(whereStatement);
//dgJEARequests.DataSource = jeaRequests;
requestList = new List<ITWebService.Requests>(jeaRequests.ToList());
dgJEARequests.DataSource = requestList;
dgJEARequests.ClearSelection();
lblCountOfRequests.Text = requestList.Count.ToString().ToString() + " requests loaded";
}
else
{
if (chkMine.Checked)
{
jeaRequests = itServices.getRequestsByAssignedToAndStatusID(JEAUser.UserName, "0");
//dgJEARequests.DataSource = jeaRequests;
requestList = new List<ITWebService.Requests>(jeaRequests.ToList());
dgJEARequests.DataSource = requestList;
dgJEARequests.ClearSelection();
}
else
{
jeaRequests = itServices.getRequestsBySQLStatement("Requests.ID > 0");
//dgJEARequests.DataSource = jeaRequests;
requestList = new List<ITWebService.Requests>(jeaRequests.ToList());
dgJEARequests.DataSource = requestList;
dgJEARequests.ClearSelection();
}
}
}
}
这是代码progressbar：
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
namespace JEAProjectManager
{
public partial class WaitProcessing : Form
{
public Action Worker
{
get;
set;
}
public WaitProcessing(Action worker)
{
InitializeComponent();
if (worker == null)
throw new ArgumentNullException();
Worker = worker;
}
protected override void OnLoad(EventArgs e)
{
base.OnLoad(e);
Task.Factory.StartNew(Worker).ContinueWith(t =>
{
this.Close();
},
TaskScheduler.FromCurrentSynchronizationContext());
}
}
}
当我单击搜索按钮时，另一个是：
private void btnSearchSelection_CheckedChanged(object sender, EventArgs e)
{
//ShowOnlyCustomSelection();
//WaitProcessing processing = new WaitProcessing();
using (WaitProcessing processing = new WaitProcessing(ShowOnlyCustomSelection))
{
processing.ShowDialog(this);
}
}
查询参数被发送到 Web 服务。我能做些什么来解决这个问题？我正在定制这个应用程序。我不是最初的开发者，但我的任务是让它变得更好。我知道那里有一些类似的错误，但情况不同。
截图：
做我的选择
传递参数进行查询
进度条
错误信息
