Multiple forms and datagridviews

[Henry Minute]

The second Form method seems to be as good as any other, from what you have told me. So on that basis. What happens when the user clicks the button, depends on whether there will only ever be one instance of Form2 where the data displayed will change depending on whatever, or whether there will be more than one instance, each one created specifically to display one set of data. If there will only be one Form2, in Form1 add

private Form2 docsForm = null;
private Form2 DocsForm
{
    get
    {
        if (this.docsForm == null)
        {
            this.docsForm = new Form2();
        }

        return docsForm;
    }
}

then whenever Form1 needs to refer to the Form2 instance just use DocsForm (the property name) NOT docsForm (the field name). This property uses what is known as 'Lazy Initialization', you can look it up later. It just means that the thing (Form2 in this case) only gets created when it needs to be. The rest of the time the existing instance is used. I have made it private deliberately. If there will be many instances of Form2 they will be created inside the click handler for the button, so the above will not be needed. The button click handler, just for illustration purposes I have called it btnShowDocs

	private void btnShowDocs\_Click(object sender, EventArgs e)
	{
                    // \*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*
                    // Only if there are to be many Form2s
                    // \*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*
		Form2 DocsForm = new Form2();
                    // \*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*
                   
                    DocsForm.DataKey = this.dataGridView1.CurrentRow.Cells\[0\].Value.ToString();
                    DocsForm.Show();  // or .ShowDialog(), depends on whether need access to Form1 again before Form2 closes 
	}

There has to be some piece of data in Form1.dgv1, that will enable Form2 to decide the correct data to show, purely for illustration I have said that that data is the value of the first column in the selected row of dgv1. But you will have to let me know what that piece of data is. It could be the value of a cell in dgv as above, or the whole row, each cell in the row determining the data for one of the dgvs of Form2. If the trigger data is not in dgv1, then what is it? Then for Form2, something like:

pu

[bwood2020]

Yes, there will only be one instance of Form 2. I have dragged and dropped a TabControl onto Form 2. Each tab contains a dgv which will be populated with a column from the dgv on Form 1. I have created a method in Form 1 that goes through each cell in row 1 and stores the new headers in an array. if it meets the criteria then it should load the Distinct values of that column into Form 2. Here is the code I have written but don't know if you can use it as it is. But maybe you can... <pre>public void button12_Click(object sender, EventArgs e)             {                                                             //MappingsForm is the name of Form 2                         MappingsForm.Show();                                  string[] HeaderArray = new string[dataGridView1.ColumnCount];                                           int n = dataGridView1.ColumnCount;                         int c = 0;                         for (c = 0; c < n; c++)                         {                               HeaderArray[c] = dataGridView1.Rows[0].Cells[c].Value.ToString();                                                             if(HeaderArray[c] == "DocType")                               {                       &nbs

[Henry Minute]

I have modified my suggestions from the previous post in light of this information, using your member names where I noticed them and some of your code, although I have suggested moving it to MappingsForm rather than having it in Form1. The reason is that in OOP programming, as far as is possible, each object (and a Form is an object) should be responsible for handling its own data and controlling access to that data. For Form1:

        private MappingsForm mappingsForm = null;
        private MappingsForm MappingsForm
        {
            get
            {
                if (this.mappingsForm == null)
                {
                    this.mappingsForm = new MappingsForm();
                }

                return mappingsForm;
            }
        }

    private void btnShowDocs\_Click(object sender, EventArgs e)
    {
            MappingsForm.DataKey = this.dataGridView1.Rows\[0\];
            MappingsForm.Show();
    }

    private void Form1\_FormClosing(object sender, FormClosingEventArgs e)
    {
        if (this.mappingsForm != null)
	{
	    this.mappingsForm.Dispose();
	    this.mappingsForm = null;
	}
    }

For MappingsForm:

public partial class MappingsForm : Form
{
	private bool dataDisplayed = false;

	public MappingsForm()
	{
	    InitializeComponent();
	}

	private void MappingsForm\_Load(object sender, EventArgs e)
	{
                if (this.dataKey != null)
                { 
	        this.LoadData();
                }
	}

	private void LoadData()
	{
	    // this is part of your code, slightly modified
                for (int c = 0; c < this.dataKey.Columns.Count; c++)
                {
                    if(this.dataKey.Cells\[c\].Value.ToString() == "DocType")
                    {
                        //pass data to dgv1
                    }
                    else if (this.dataKey.Cells\[c\].Value.ToString() == "PurposeType") // else here to avoid unnecessary processing
                    {
                        //pass data to dgv2
                    }
                    else if (this.dataKey.Cells\[c\].Value.ToString() == "SomeOtherType") // else here to avoid unnecessary processing
                    {
                        // and so on 
                    }

                    // This could also be written like this, so either have t

[bwood2020]

Thanks Henry for the short run down of your concerns. I will look into this... I agree with you about renaming the controls as descriptive as possible. As soon as I get this last part I will go back through and rename them. I implemented the code you wrote and I get the error 'System.Windows.Forms.DataGridViewRow' does not contain a definition for 'Columns'. This occurs at 'this.dataKey.Columns.Count' in the for loop on Form 2. I have tried looking this up and I get similar hits but what I have tried doesn't work. Any ideas?

[Henry Minute]

Oops. :-O I'm having a root round. I'll get back to you.

Henry Minute Do not read medical books! You could die of a misprint. - Mark Twain Girl: (staring) "Why do you need an icy cucumber?" “I want to report a fraud. The government is lying to us all.”

[Henry Minute]

Try changing Columns for Cells. It should work exactly the same. Only The DataGridView has Columns, each of it's rows contains a cell for each of the columns.

Henry Minute Do not read medical books! You could die of a misprint. - Mark Twain Girl: (staring) "Why do you need an icy cucumber?" “I want to report a fraud. The government is lying to us all.”

[bwood2020]

Hi Henry, I have tried to pass dataKey.Cells[c].Value a couple of ways but I am not having any luck. Here are just three ways I have tried that make sense to me but aren't working: dataGridView1.DataSource = dataKey.Cells[c].Value; dataGridView1.Rows.Add(dataKey.Cells[c].Value); dataGridView1.SelectedRows[c].Cells[c].Value = dataKey.Cells[c].Value; I have also tried adding ToString() to the end of Value and that isn't working either. I have spent a good amount of time doing research on how to pass the values of the cells to the dgv and I haven't found anything that would work. Do you have a little more time to help me out on this? Thank you, Brenton

[Henry Minute]

Hi Brenton, None of the options that you have tried will work. I'll try to explain. As we left it, MappingForm has a DataViewRow containing a series of cells, each cell holding something like "thisType" or "thatType". To populate each of your DataGridViews with relevant information you need to get it from a file, in the same way that you did for the dgv on Form1. Only you know which file contains data for "thisType" and which file holds data for "thatType". The if (dataKey.cells[c].Value.ToString == "thisType") lines (or the switch block, if that is what you used), simply enables you differentiate between the various 'Types' so that you know which to use the in the SELECT statement when retrieving the data into a DataTable/DataSet or whatever you decide to use as the datasource for your dgvs. Something like

SELECT * FROM TheThisTypeFile.csv
WHERE DataType == "thisType"

Obviously the WHERE clause is only required if that file holds data for various 'Types'. Hope that helps.

Henry Minute Do not read medical books! You could die of a misprint. - Mark Twain Girl: (staring) "Why do you need an icy cucumber?" “I want to report a fraud. The government is lying to us all.”

[bwood2020]

I am still confused because I would still have to know what the field names are called in the file. For instance, I have 2 files. One file may have 32 fields and the other 10 fields which come in different days (say one today and one tomorrow). In these columns we are looking for Loan Purpose Type and Loan Documentation type. In file one these fields are named Doc Type and Purp Type and in the second file they are named Documentation Type and Purpose Type. Also, in the where clause you would need to specify all the doc types. However, each client has there own doc types. One client may have say Full Doc, Limited Doc, and No Doc. Another client may have 1, 2, and 3. so it seems the query would have to change every time. Is this correct?

[Henry Minute]

Ah-ha! I am beginning to understand a little more about how this is supposed to work. If I am right, probably not, but here goes anyway, the purpose of the dgv in Form1 is to allow for translation/modification of what is in the files from client, to a 'standard' wording. If I have got that right, you have been doing things backwards! :laugh: Sorry, I shouldn't laugh, but it is just the sort of thing I do all the time. I will wait for your response before going further.

Henry Minute Do not read medical books! You could die of a misprint. - Mark Twain Girl: (staring) "Why do you need an icy cucumber?" “I want to report a fraud. The government is lying to us all.”

[bwood2020]

That is correct, with one exception. The only thing I want to accomplish in Form 1 is changing the field headers to a standardized naming convention. In Form 2 I want to standardize the data (but this only needs to be done to certain fields like Doc types). I will explain more to you so we are both on the same page. So we receive files on a daily basis from many different clients. These files contain different information in different columns with different field headers. We use SSIS to get them into our systems however, SSIS breaks every time we run the files through because of the differentiation between field headers and data. So, to get around this I am creating a prototype to standardize all the files which mainly include field headers and data related to some of the fields (i.e. Doc Type, Purpose Type, and so on). So For example, if the field header Doc Type comes in then in form 1 row 1 of the dgv there is a combo dropdown where the user can select the "New" header name. Then the second form needs to include the distinct data for the specific field headers so I can standardize them as well. This second form will activate upon clicking a button. Example: File 1: Loan Documentation Type(field name from file) = DocType(new header that will be selected in row 1 of the dgv on Form1) Low Doc, Full, and No Doc(Doc Types data from file) = L, F, ND(translate doc types to standardized naming convention in dgv on Form 2) File 2: Docs(field name from file) = DocType(new header that will be selected in row 1 of the dgv on Form1) 1, 2, and 3 (data from file) = L, F, ND(translate doc types to standardized naming convention in dgv on Form 2) So the files we get have 100's of loans. For this example, the field Doc Types can have many types (i.e. 50 Full docs, 25 Low Docs, and 25 No docs) which is why I would like to select Distinct values only having to map, in this case, 3 doc types rather then 100. I am sure I have not explained myself very well in previous posts so please let me know if you need additional information or if you are confused on anything I have said to this point.

[Henry Minute]

Going back to your previous post, you have said that for documentation type a client might have Full Doc, Limited Doc and No Doc; whilst another might have 1, 2 and 3. Are the options finite? i.e. are there always 3 possibilities for documentation type, and is that the same for all fields? (not necessarily 3, it could be 10, 7 or whatever) The point is are all options (or at least the number of possible options) known to yourselves prior to recieving the file(s). Also will the same client always use the same headings. On to this post. I am not 100% on the reason for the multiple dgvs on the mapping form. In Mapping form, is the purpose of the different dgvs to collate, based on documentation type (dgv1 = full doc, dgv2 = limited doc etc), or to summarise (dgv1 = doctype, with a row for count of full doc, another for count of limited doc etc) with the other dgvs for the other field types. Is the final objective to just display the data, to stream it to another application or to write it back out to a file and if so what type of file (.csv, mdf, txt) The point I made previously (about doing it backwards) is that to do anything with the clients data, whether selecting on a field type, collating on a field type, or whatever, you have at that stage to use the clients wording/coding scheme.

Henry Minute Do not read medical books! You could die of a misprint. - Mark Twain Girl: (staring) "Why do you need an icy cucumber?" “I want to report a fraud. The government is lying to us all.”

[bwood2020]

No, there could be up to 30+ different doc types. I just used three for this example. Same goes for the other fields we need to map data for. Not all possible data is known until we receive the data and the same client doesn't always give us the same headings or file formats. nothing is considered finite between the data or the headers. The reason for the multiple dgv's is to have a dgv per field where the data needs to be mapped. So, dgv1 is for Doc Types, dgv2 is for Purpose Types, dgv3 is for Occupancy Types and so on. So the second part of the third paragraph you wrote is correct "or to summarize (dgv1 = doctype, with a row for count of full doc, another for count of limited doc etc) with the other dgvs for the other field types". So the all the dgv's have three columns. The first will be the column that gets populated with the data from the file or the dgv on Form 1(example Full Documentation). The second column is a combo dropdown that contains the new code (F for Full Documentation). The third is a count of how many loans have Full Documentation. After all Doc Types have been recoded, then dgv on Form 1 needs to be updated. For example, Full Documentation is will be updated to F. Once the dgv on Form 1 has been updated with the new codes from form 2, I will output it to excel for our SSIS (this is done and has been tested).

[Henry Minute]

Hi there. I have been thinking about this and have made a simple demo of something that I think might work. If you have the time would you give it a quick whirl to see if it might suit. The demo consists of two forms each having a datagridview and a button, you will be able to work out the names of these controls from the code I will post. I will post the code for the two forms in separate posts, as it would otherwise be a very long post. This is the test data I have used for the demo and if you could save it as TestData.csv in the directory with the executable for the demo, normally 'application-files-directory\bin\debug' TestData.csv

Prop, Offer, Docs, Gtee, Figs
house, no, full, none, true
flat, true, part, complete, no
appt, no, no, yes, yes
bungalow, yes, full, no, no
mais, false, yes, no, comp

The code for the first form follows shortly.

Henry Minute Do not read medical books! You could die of a misprint. - Mark Twain Girl: (staring) "Why do you need an icy cucumber?" “I want to report a fraud. The government is lying to us all.”

[Henry Minute]

Code for the first form.

public partial class ListEditorForm : Form
{
	List<string> standardList = new List<string>();
	Dictionary<string, string> headers = new Dictionary<string, string>();
	DataSet headerDataSet = null;
	DataTable headerTable = null;
	MappingForm mappingForm = null;
	readonly string dataFile = "TestData.csv";

	FieldMappingDictionary docsDictionary = null;

	public ListEditorForm()
	{
		InitializeComponent();
		InitStandardList();
	}

	private void InitStandardList()
	{
		standardList.AddRange(new string\[\] { "Property", "Offer", "Documentation", "Figures", "Guarantee" });
	}

	private void ProcessMods()
	{
		// Create a copy of original table structure with
		// standardized column names\*\*
		// load original file data into it
		// then do a series of updates using the docsDictionary, and the
		// other Dictionaries
		// STEP THROUGH THIS TO WATCH UPDATE STATEMENT BUILDING
		StringBuilder selectBuilder = null;
		foreach (string key in this.docsDictionary.Keys)
		{
			foreach (string val in this.docsDictionary\[key\])
			{
				selectBuilder = new StringBuilder();
				selectBuilder.Append("UPDATE <yourtablenamehere\*\*> SET Documentation = ");
				selectBuilder.Append(key);
				selectBuilder.Append(" WHERE Documentation = ");
				selectBuilder.Append(val);

				string updateQuery = selectBuilder.ToString();

				// execute the query here
				// you know OleDbConnection, OleDbcommand etc.
				// then go round for next mod
			}
			// go round for next key
		}

		// then do same for next dictionary
	}

	private Dictionary<string, string> MakeHeaderDictionary()
	{
		Dictionary<string, string> result = new Dictionary<string, string>();
		foreach (DataRow row in this.headerTable.Rows)
		{
			result.Add(row\[1\].ToString(), row\[0\].ToString());
		}

		return result;
	}

	#region ListEditorForm PROPERTIES ...............................
	public Dictionary<string, string> Headers
	{
		get
		{
			return this.headers;
		}

		private set
		{
			this.headers = value;
		}
	}

	private MappingForm MappingForm
	{
		get
		{
			if (this.mappingForm == null)
			{
				this.mappingForm = new MappingForm();
			}

			return this.mappingForm;
		}
	}
	#endregion ListEditorForm PROPERTIES

	private void ListEditorForm\_Load(object sender, EventArgs e)
	{
		string headerLine;
		using (StreamReader

[Henry Minute]

Code for second form.

public partial class MappingForm : Form
{
	List<string> standardDocumentList = new List<string>();
	FieldMappingDictionary documentsDictionary = new FieldMappingDictionary();

	private Dictionary<string, string> headerDictionary = null;
	private string dataFile;

	public MappingForm()
	{
		InitializeComponent();

		InitLookupLists();
	}

	private void InitLookupLists()
	{
		this.standardDocumentList.AddRange(new string\[\] { "Full", "Partial", "None" });
	}

	private void MappingForm\_Load(object sender, EventArgs e)
	{
		DataGridView dgv = null;
		string headerString = null;

		foreach (string key in this.headerDictionary.Keys)
		{
			headerString = this.headerDictionary\[key\];
			switch (key)
			{
				case "Documentation":
					dgv = this.dgvDocumentation;
					break;
				case "Property":
					dgv = null;
					break;
				case "Offer":
					dgv = null;
					break;
				case "Figures":
					dgv = null;
					break;
				case "Guarantee":
					dgv = null;
					break;
			}

			if (dgv != null)
			{
				this.FillDatagrid(headerString, dgv);
			}
		}
	}

	DataTable dFill = null;
	private void FillDatagrid(string headerString, DataGridView dgv)
	{
		//Connect to csv file
		String comString = @"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" +
			Path.GetDirectoryName(Path.GetFullPath(this.dataFile)) + @";Extended Properties=""Text;HDR=YES;FMT=Delimited;IMEX=1\\""";

		String strSql = "SELECT DISTINCT " + headerString + " FROM \[" + Path.GetFileName(this.dataFile) + "\]";
		using (OleDbConnection conCSV = new OleDbConnection(comString))
		{
			conCSV.Open();
			OleDbCommand dbCommand = new OleDbCommand(strSql, conCSV);
			OleDbDataAdapter dAdapter = new OleDbDataAdapter(dbCommand);
			dFill = new DataTable();
			dAdapter.Fill(dFill);
		}

		bindingSource1.DataSource = dFill;
		dgv.DataSource = bindingSource1;

		// Set up lookup for dgvDocumentation
		// only temporarilly here for demo
		DataGridViewComboBoxColumn lookupColumn = new DataGridViewComboBoxColumn();
		this.dgvDocumentation.Columns.Add(lookupColumn);
		lookupColumn.ValueType = typeof(string);
		lookupColumn.HeaderText = "Standard";
		lookupColumn.DataSource = this.standardDocumentList;

		for (int i = 0; i < dgv.Columns.Count; i++)
		{
			dgv.Columns\[i\].SortMode = DataGridViewColumnSortMode.NotSortable;
			dgv.Columns\[i\].AutoSizeMode = DataGridViewAutoSizeColumn

[Henry Minute]

public class FieldMappingDictionary : Dictionary>
{
public void Add(string key, string value)
{
// if the key is already in the list
if (base.Keys.Contains(key))
{
// only do it if not already there
if (!base[key].Contains(value))
{
// add the new value
base[key].Add(value);
}
}
else
{
// if the key ain't there, add it and a new values list
List list = new List();
list.Add(value);
base.Add(key, list);
}
}
}

This is just a collection used in the demo. Look forward to hearing from you.

Henry Minute Do not read medical books! You could die of a misprint. - Mark Twain Girl: (staring) "Why do you need an icy cucumber?" “I want to report a fraud. The government is lying to us all.”

[bwood2020]

Looking into this now...

[bwood2020]

Hi Henry, have a good weekend? I copied the code into two forms but I'm getting an error in the collection code you sent over. The errors I'm getting are: 1. expected { 2. Invalid token '>' in class, struct, or interface member declaration. The error occurs at: public class FieldMappingDictionary : Dictionary> I placed this code outside the public partial class ListEditorForm : Form. Should I place this code somewhere else? Also, looks like I have a couple of things coming down the pipe today so I may be fairly busy today. Just want you to know incase you don't hear back from me until later today. Thank you, Brenton Brenton

[Henry Minute]

Yes thanks, very restful. I am a silly boy. The errors are because in the reply box if you paste a < the editor replaces it with the html equivalent and the same with >. If you replace all the '& gt;' with > and '& lt;' with <. all should be well.

Henry Minute Do not read medical books! You could die of a misprint. - Mark Twain Girl: (staring) "Why do you need an icy cucumber?" “I want to report a fraud. The government is lying to us all.”