当datasource属性设置错误时，无法修改项集合 [英] Items collection cannot be modified when the datasource property is set error

问题描述

我有两个窗口窗口



错误显示我需要从文本框中的Windows form2传递数据



到windows form1组合框



第一个窗体



找到windows form1中的组合框，我在表格的加载事件中显示数据

I have two windows form

error show when i need to pass data from windows form2 in textbox

to windows form1 combobox

First windows Form

found combobox inside windows form1 and I show data in it in load event of form

public DataTable ShowExceltwoLanguage()
{

            OleDbConnection con = new OleDbConnection(connection);


            con.Open();
            string str = "select MemberID,MemberNameAR + ' - ' + MemberNameEN as MemberName from [MemberAR$]";
            OleDbCommand com = new OleDbCommand();
            com = new OleDbCommand(str, con);
            OleDbDataAdapter oledbda = new OleDbDataAdapter();
            oledbda = new OleDbDataAdapter(com);
            DataSet ds = new DataSet();
            ds = new DataSet();
            oledbda.Fill(ds, "[MemberAR$]");
            con.Close();
            DataTable dt = new DataTable();
            dt = ds.Tables["[MemberAR$]"];
            return dt;


}

在windows form1的加载事件中
我写如下

in load event of windows form1 i write as following

QrClasses qrc = new QrClasses();
  DataTable dt = qrc.ShowExceltwoLanguage();
  comboBox4.DataSource = dt;
  comboBox4.DisplayMember = "MemberName";
  comboBox4.ValueMember = "MemberID";

第二个窗口形式



这里是错误



设置DataSource属性时无法修改项目集合显示


$ 2 $ b在button2点击事件的按钮1中

Second windows form

here is error

Items collection cannot be modified when the DataSource property is set show

in button1 of form2 click event

if (!string.IsNullOrWhiteSpace(textBox1.Text))
                {

                       
                        var cb = ((Form1)Owner).comboBox4;
                        var index = cb.FindString(textBox1.Text);
                        if (index == -1)
                        {
                            cb.Items.Add(textBox1.Text);// in this line Additional information: Items collection cannot be modified when the DataSource property is set.
                            index = cb.FindString(textBox1.Text);
                            if (index > -1)
                            {
                                cb.SelectedIndex = index;
                                Close();
                            }
                        }
                        else
                        {

                            cb.SelectedIndex = index;
                        }
                    }

以便在可能的情况下如何解决？



我尝试了什么：

so that how to solve that if possible ?

What I have tried:

Items collection cannot be modified when the DataSource property is set Error

推荐答案

;
OleDbCommand com = new OleDbCommand（）;
com = new OleDbCommand（str，con）;
OleDbDataAdapter oledbda = new OleDbDataAdapter（）;
oledbda = new OleDbDataAdapter（com）;
DataSet ds = new DataSet（）;
ds = new DataSet（）;
oledbda.Fill（ds， [MemberAR

"; OleDbCommand com = new OleDbCommand(); com = new OleDbCommand(str, con); OleDbDataAdapter oledbda = new OleDbDataAdapter(); oledbda = new OleDbDataAdapter(com); DataSet ds = new DataSet(); ds = new DataSet(); oledbda.Fill(ds, "[MemberAR

< /跨度>）;
con.Close（）;
DataTable dt = new DataTable（）;
dt = ds.Tables [ [MemberAR

"); con.Close(); DataTable dt = new DataTable(); dt = ds.Tables["[MemberAR

< /跨度>];
return dt;


}

"]; return dt; }

在windows form1的加载事件中
我写如下

in load event of windows form1 i write as following

QrClasses qrc = new QrClasses();
  DataTable dt = qrc.ShowExceltwoLanguage();
  comboBox4.DataSource = dt;
  comboBox4.DisplayMember = "MemberName";
  comboBox4.ValueMember = "MemberID";

第二个窗口形式



这里是错误



设置DataSource属性时无法修改项目集合显示


$ 2 $ b在button2点击事件的按钮1中

Second windows form

here is error

Items collection cannot be modified when the DataSource property is set show

in button1 of form2 click event

if (!string.IsNullOrWhiteSpace(textBox1.Text))
                {

                       
                        var cb = ((Form1)Owner).comboBox4;
                        var index = cb.FindString(textBox1.Text);
                        if (index == -1)
                        {
                            cb.Items.Add(textBox1.Text);// in this line Additional information: Items collection cannot be modified when the DataSource property is set.
                            index = cb.FindString(textBox1.Text);
                            if (index > -1)
                            {
                                cb.SelectedIndex = index;
                                Close();
                            }
                        }
                        else
                        {

                            cb.SelectedIndex = index;
                        }
                    }

以便在可能的情况下如何解决？



我尝试了什么：

so that how to solve that if possible ?

What I have tried:

Items collection cannot be modified when the DataSource property is set Error

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