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Change visible state of DataGridView only given its name

I have a form application where multiple DataGridView objects are to be displayed (but not at once). They should be created on top of each other and it should then be possible to toggle the displayed DataGridView using a ComboBox.
I have a function which should create new DataGridView every time its called and then adds the name to the ComboBox:
private void readCSV(string DBname)
{
DataGridView tagDBname = new DataGridView();
tagDBname.Location = new System.Drawing.Point(24, 260);
tagDBname.Name = DBname;
tagDBname.Size = new System.Drawing.Size(551, 217);
tagDBname.TabIndex = 6;
tagDBname.Columns.Add("Column1", "Col1");
tagDBname.Columns.Add("Column2", "Col2");
tagDBname.Visible = false;
comboBoxTag.Items.Add(DBname);
}
Then I would like to change the visibility state of a DataGridView given the selected name from the ComboBox. This should be done in the function called when the index changes:
private void comboBoxTag_SelectedIndexChanged(object sender, EventArgs e)
{
// Get the name of the DataGridView which should be visible:
string selectedTagDB = comboBoxTagDatabases.SelectedItem.ToString();
DataGridView tagDatabase = ? // Here the DataGridView should be selected given the name "selectedTagDB"
tagDatabase.Visible = true;
}
In the above, I do not know how to assign the DataGridView only given its name. Any help would be appreciated - even if it means that the selected approach is inappropriate of what I am trying to achieve. If the question is answered elsewhere, feel free to guide me in the right direction :)

I would store the gridviews in a dictionary by using the DB name as key;
private readonly Dictionary<string, DataGridView> _tagDBs =
new Dictionary<string, DataGridView>();
private void readCSV(string DBname)
{
DataGridView tagDBname = new DataGridView();
// Add the gridview to the dictionary.
_tagDBs.Add(DBname, tagDBname);
tagDBname.Name = DBname;
tagDBname.Location = new System.Drawing.Point(24, 260);
tagDBname.Size = new System.Drawing.Size(551, 217);
tagDBname.TabIndex = 6;
tagDBname.Columns.Add("Column1", "Col1");
tagDBname.Columns.Add("Column2", "Col2");
tagDBname.Visible = false;
this.Controls.Add(tagDBname); // Add the gridview to the form ot to a control.
comboBoxTag.Items.Add(DBname);
}
private void comboBoxTag_SelectedIndexChanged(object sender, EventArgs e)
{
// Get the name of the DataGridView which should be visible:
string selectedTagDB = comboBoxTagDatabases.SelectedItem.ToString();
foreach (DataGridView dgv in _tagDBs.Values) {
dgv.Visible = dgv.Name == selectedTagDB; // Hide all gridviews except the selected one.
}
}
If you need to do something with the selected gridview, you can get it with:
if (_tagDBs.TryGetValue(selectedTagDB, out DataGridView tagDatabase)) {
// do something with tagDatabase.
}
Note: you must add the gridview to the form or to a container control on the form. E.g.
this.Controls.Add(tagDBname);

You can loop through all DataGridViews of the form to display the expected one using its name, while hidding the others ones.
This solution isn't pretty but works
private void ShowOneDataGridViewAndHideOthers(string name)
{
foreach (var DGV in this.Controls.OfType<DataGridView>())
{
DGV.Visible = DGV.Name == name;
}
}
And call it this way :
private void comboBoxTag_SelectedIndexChanged(object sender, EventArgs e)
{
// Get the name of the DataGridView which should be visible:
string selectedTagDB = comboBoxTagDatabases.SelectedItem.ToString();
ShowOneDataGridViewAndHideOthers(selectedTagDB);
}
The method can be made a bit more generic this way :
private void ShowOneControlAndHideOthers<T>(string name, Control controls) where T : Control
{
foreach (var control in controls.Controls.OfType<T>())
{
control.Visible = control.Name == name;
}
}
private void comboBoxTag_SelectedIndexChanged(object sender, EventArgs e)
{
// Get the name of the DataGridView which should be visible:
string selectedTagDB = comboBoxTagDatabases.SelectedItem.ToString();
ShowOneControlAndHideOthers<DataGridView>(selectedTagDB, this);
}

DataGridView not loading data programmatically

I am working on a Windows application where I get an input from a TextBox and add it to the DataGridView when user clicks on a Button (Add).
My problem is that when I add the text for the first time, it works fine and its added to the grid.
When I add new text, it's not added to the DataGridView. Once the Form is closed and reopened with the same object then I am able to see it.
Code:
private void btnAddInput_Click(object sender, EventArgs e)
{
if (Data == null)
Data = new List<Inputs>();
if (!string.IsNullOrWhiteSpace(txtInput.Text))
{
Data.Insert(Data.Count, new Inputs()
{
Name = txtInput.Text,
Value = string.Empty
});
}
else
{
MessageBox.Show("Please enter parameter value", "Information", MessageBoxButtons.OK, MessageBoxIcon.Information);
}
txtInput.Text = "";
gridViewInputs.DataSource = Data;
}
I am not sure what is causing the record not to be added to grid on second add button click.

You could set the DataGridView.DataSource to null before setting a new one.
This would cause the DataGridView to refresh its content with the new data in the source List<Inputs>:
the underlying DataGridViewDataConnection is reset only when the DataSource reference is different from the current or is set to null.
Note that when you reset the DataSource, the RowsRemoved event is raised multiple times (once for each row removed).
I suggest to change the List to a BindingList, because any change to the List will be reflected automatically and because it will allow to remove rows from the DataGridView if/when required: using a List<T> as DataSource will not allow to remove a row.
BindingList<Inputs> InputData = new BindingList<Inputs>();
You can always set the AllowUserToDeleteRows and AllowUserToAddRows properties to false if you don't want your Users to tamper with the grid content.
For example:
public class Inputs
{
public string Name { get; set; }
public string Value { get; set; }
}
internal BindingList<Inputs> InputData = new BindingList<Inputs>();
private void Form1_Load(object sender, EventArgs e)
{
dataGridView1.DataSource = InputData;
}
private void btnAddInput_Click(object sender, EventArgs e)
{
string textValue = txtInput.Text.Trim();
if (!string.IsNullOrEmpty(textValue))
{
InputData.Add(new Inputs() {
Name = textValue,
Value = "[Whatever this is]"
});
txtInput.Text = "";
}
else
{
MessageBox.Show("Not a valid value");
}
}
If you want to keep using a List<T>, add the code required to reset the DataGridView.DataSource:
private void btnAddInput_Click(object sender, EventArgs e)
{
if (!string.IsNullOrEmpty(textValue))
{
//(...)
dataGridView1.DataSource = null;
dataGridView1.DataSource = InputData;
txtInput.Text = "";
}
//(...)

Retrieve value from dynamic dropdownlist in placeholder C#

I have dynamic drop down lists that are created based on what's selected in the list box.. When clicking confirm this is when the drop down lists are created. Clicking save is where I attempt to retrieve the values. However I am unable to retrieve that values that are in the drop down lists.
Code:
protected void btnConfirm_Click(object sender, EventArgs e)
{
int ID = 0;
foreach (string value in values)
{
MyStaticValues.alEdit.Add(value);
CreateEditForm(value, ID);
ID += 1;
}
if (values.count != 0)
{
btnSave.Visible = true;
btnConfirm.Enabled = false;
}
}//End of btnConfirm_Click
protected void CreateEditForm(string Value, int ID)
{//Creates an edit form for the value inserted.
string name = value;
//This part adds a header
phEditInventory.Controls.Add(new LiteralControl("<h2>" + name + "</h2>"));
phEditInventory.Controls.Add(new LiteralControl("<div class=\"clearfix\"></div>"));
//Create a label
Label lblName = new Label();
lblName.Text = "Name";
lblName.ID = "lblName" + ID;
lblName.CssClass = "control-label";
//Create a Drop Down List
DropDownList ddlName = new DropDownList();
ddlName.ID = "ddlName" + ID;
ddlName.CssClass = "form-control";
//Set default N/A Values For Drop Down List
ddlName.Items.Add(new ListItem("N/A", Convert.ToString("0")));
//The Rest of the Values are populated with the database
//Adds the controls to the placeholder
phEditInventory.Controls.Add(lblName);
phEditInventory.Controls.Add(ddlName);
phEditInventory.Controls.Add(new LiteralControl("<div class=\"clearfix\"></div>"));
} //End of CreateEditForm
protected void btnSave_Click(object sender, EventArgs e)
{
string name = "";
try
{
for (int i = 0; i < MyStaticValues.alEdit.Count; i++)
{
string nameID = "ddlName" + i.ToString();
DropDownList ddlName = (DropDownList)phEditInventory.FindControl(nameID);
name = ddlName.SelectedValue.ToString();
}
}
catch (Exception ex)
{
}
phEditInventory.Visible = false;
btnSave.Visible = false;
MyStaticValues.alEdit.Clear();
}//End of btnSave_Click Function

Your problem is that the dynamically created dropdown lists are not maintained on postback. When you click the Save button, a postback occurs, and the page is re-rendered without the dynamically created dropdowns. This link may help.
Maintain the state of dynamically added user control on postback?

DataGridView is not updating after second row

i am trying a few things in WinForms for the first time. I have a problem which appears very trivial to me but then i am not a WinForms guy.. searched a lot but could not find the solution.
Below is the code, don't worry about the content itself, its just test code. The problem is that when i click the AddNew button a row gets added to gridview but after that no row gets added, no matter how many times user clicks on the AddNew button. You can see that in the Image below.
Can you point out why no rows are getting added to the gridview after a row has been added.
AddNew button just works for one click. While as it should add the second row again and again.
Thanks in advance.
public partial class JobCard : UserControl
{
List<Work> works = new List<Work>();
BindingSource bs = new BindingSource();
public JobCard()
{
InitializeComponent();
works.Add(new Work() { S_No = 1, JobCategoryId = 1, JobCategoryName = "electricals", JobId = 1, JobName = "lights", Labour = 1, MaterialName = "tape", PartName = "headlight" });
bs.DataSource = works;
dataGridView1.AutoGenerateColumns = true;
dataGridView1.DataSource = bs;
}
private void btnAddNew_Click(object sender, EventArgs e)
{
works.Add(new Work() { S_No = 2, JobCategoryId = 2, JobCategoryName = "electricals", JobId = 2, JobName = "lights", Labour = 2, MaterialName = "tape", PartName = "headlight" });
dataGridView1.DataSource = works;
}
}

You need to reset the datasource of your bindingsource.
Try
private void btnAddNew_Click(object sender, EventArgs e)
{
...
bs.DataSource = null;
bs.DataSource = works;
}

Add a row to existing databound datagridview

In my Windows application I had a job code combobox and when user selects a jobcode from the combobox it will get the corresponding data from database and will display it in a datagridview below the combobox. All is fine and I am able to load data corresponding to selected jobcode.
I used the this code
public void loadcompljobcodecombobox()
{
completedcobcodeadapterTableAdapter cmpltjbcd = new completedcobcodeadapterTableAdapter();
cmpltjbcd.Connection = new OleDbConnection(Program.ConnStr);
DataTable dt= cmpltjbcd.GetData(int.Parse(cmbcutcode.SelectedValue.ToString()));
if (dt.Rows.Count > 0)
{
cmbjobcode.ValueMember = "jobpk";
cmbjobcode.DisplayMember = "jobcode";
txtcompanyname.Text = "companyname";
cmbjobcode.DataSource = dt;
}
else
{
MessageBox.Show("NO JobCode to be invoiced");
}
}
private void cmbjobcode_SelectedValueChanged(object sender, EventArgs e)
{
tbltoinvoicedtableTableAdapter tbltoinvce = new tbltoinvoicedtableTableAdapter();
tbltoinvce.Connection = new OleDbConnection(Program.ConnStr);
if (cmbjobcode.SelectedValue != null)
{
DataTable dt = tbltoinvce.GetDataBy(int.Parse(cmbjobcode.SelectedValue.ToString()));
dataGridView1.DataSource = dt;
}
}
Now my requirement is user must be able to select more than one jobcode details at a time for invoicing i.e. if he selects one value from jobcode corresponding data should be added in datagridview and when he select another jobcode its corresponding data should be added as next row in the Datagridview.
I had tried very much and find no way can anyone suggest an idea or example

If I understand you correctly, I would try something like this. This isn't tested but it's an idea.
At Form Level:
private BindingList<DataRow> jobList;
Then to add to your current code...
private void cmbjobcode_SelectedValueChanged(object sender, EventArgs e)
{
tbltoinvoicedtableTableAdapter tbltoinvce = new tbltoinvoicedtableTableAdapter();
tbltoinvce.Connection = new OleDbConnection(Program.ConnStr);
if (cmbjobcode.SelectedValue != null)
{
DataRow job = tbltoinvce.GetDataBy(int.Parse(cmbjobcode.SelectedValue.ToString())).Rows[0];
if (jobList == null)
{
jobList = new BindingList<DataRow>();
jobList.Add(job);
dataGridView1.DataSource = jobList;
}
else
{
if (!jobList.Contains(job));
jobList.Add(job);
}
}
}
**Edit: This is assuming your job data contains only one row of data since your question asked for how to add "a row".