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Check value of datatable with C#

I want to check if values of datatable of the same column are equals to "int" or not , so if it's true i want to calculate with content value the sum. This is my code which return always when i click on sum button "pas tous entier" .
Thank you in advance!
private void button7_Click(object sender, EventArgs e)
{
int i = 0, s = 0;
String type ="int";
DataTable dt = new DataTable("Table_insertion");
bool exists = dt.AsEnumerable().Any(row => type == row.Field<String>("Type"));
if (exists== true)
{
for (i = 0; i < dataGridView1.Rows.Count; ++i)
{
s += Convert.ToInt32(dataGridView1.Rows[i].Cells[2].Value);
}
label5.Text = s.ToString();
}
else
{
MessageBox.Show("pas tous entiers");
}
}

The datatable seems unnecessary here.
Maybe the following is enough.
for (i = 0; i < dataGridView1.Rows.Count; ++i)
{
var str = dataGridView1.Rows[i].Cells[2].Value?.ToString();
if( !string.IsNullOrEmpty(str) && Int32.TryParse(str, out var parsed)
{
s += parsed;
}
}
If you want to check the type of the column in a datatable you can check its DataType.
foreach (var col in datatable1.Columns)
{
if ( col.DataType == typeof(System.Int16) || col.DataType == typeof(System.Int32)) // Or other types
{
....

Are you just trying to evaluate if the string returned contains only numbers? If so, you may want to use a regex match on the data. There is a great example here: Regex for numbers only

How do I set specific columns in a DataGridView to 0 if it is blank?

In this example I am looping through each cell individually.
However, I have a name column and another optional column which I want to avoid. So I'd rather want to loop through a specific set of columns without the optional one instead but I'm not sure how.
This is how I did the thorough sweep:
foreach (DataGridViewRow row in DGVExcel.Rows)
{
for (int i = 0; i < row.Cells.Count; i++)
{
if (row.Cells[i].Value == null || row.Cells[i].Value == DBNull.Value ||
String.IsNullOrWhiteSpace(row.Cells[i].Value.ToString()))
{
row.Cells[i].Value = 0;
//DGVExcel.RefreshEdit();
}
}
}

However, I have a name column [...] so I'd rather'd loop through specific columns instead
If I understand you correctly you could get the index of the column and you can skip one for-loop:
int colindex = DGVExcel.Columns["SpecificColumnName"].Index;
foreach (var row in DGVExcel.Rows)
{
if (row.Cells[colindex].Value == null || row.Cells[colindex].Value == DBNull.Value ||
String.IsNullOrWhiteSpace(row.Cells[colindex].Value.ToString()))
{
row.Cells[colindex].Value = 0;
//DGVExcel.RefreshEdit();
}
}
EDIT
Is there a way to list the excluded columns instead of the included ones, because listing each one would be messy
In this case I would leave it with 2 for-loops. Basically you could save all the names in a List and check whether it contains the name of the current column and if it doesn't then you can do your 0 replacement.
List<string> ExcludedColumnsList = new List<string> { "ExcludedColumnName_1", "ExcludedColumnName_2" };
foreach (DataGridViewRow row in DGVExcel.Rows)
{
for (int i = 0; i < row.Cells.Count; i++)
{
if (!ExcludedColumnsList.Contains(DGVExcel.Columns[i].Name))
{
if (row.Cells[i].Value == null || row.Cells[i].Value == DBNull.Value ||
String.IsNullOrWhiteSpace(row.Cells[i].Value.ToString()))
{
row.Cells[i].Value = 0;
//DGVExcel.RefreshEdit();
}
}
}
}
Another option could also be to use linq. Get all indices except the excluded columns and foreach only through those:
List<string> ExcludedColumnsList = new List<string> { "ExcludedColumnName_1", "ExcludedColumnName_2" };
List<int> indexList = dataGridView1.Columns.Cast<DataGridViewColumn>()
.Where(x => !ExcludedColumnsList.Contains(x.Name))
.Select(x => x.Index).ToList();
foreach (DataGridViewRow row in DGVExcel.Rows)
{
foreach (int i in indexList)
{
if (row.Cells[i].Value == null || row.Cells[i].Value == DBNull.Value ||
String.IsNullOrWhiteSpace(row.Cells[i].Value.ToString()))
{
row.Cells[i].Value = 0;
//DGVExcel.RefreshEdit();
}
}
}

How To Compare a Textbox With An Array in C#

I'm pretty new in C# and i couldn't find an answer for this.
I'm getting the values of a column named NUMERO_CTA from my DB in an array within valores variable. But I have to compare this array of values with a textbox to check if one of the values contained in valores matches with the value of the textbox named txtCuentaDestino. How can I compare a textbox.text with an array?. Thanks in advanced!
Here's my code:
DataTable tbl = ds.Tables[0];
for (int i = 0; i < tbl.Rows.Count; i++)
{
DataRow myRow = tbl.Rows[i];
valores = new string[] {myRow["NUMERO_CTA"].ToString()};
}
if (ds.Tables[0].Rows.Count == 0)
{
GuardaCuenta();
return false;
}
else if (txtCuentaDestino.Text == resultado)
{
return true;
}
else
{
return false;
}

You can't compare an array of strings and a string. You want to compare the string from the textbox to each string in your array, one at a time.
In this case if you want to check if there is a string in the array which matches your textbox string you can use the linq method Contains.
Ex.
if (arrayOfStrings.Contains(singleString))
{
// Do something
}

you need to iterate over the valores array and make the comparison.
foreach(string s in valores)
{
if(s == txtCuentaDestino.Text)
{
//do something magical
}
}

Thanks for the answers:
Both helped me a lot! Here is the result:
for (int i = 0; i < tbl.Rows.Count; i++)
{
DataRow myRow = tbl.Rows[i];
valores = new string[] { myRow["NUMERO_CTA"].ToString() };
foreach (string x in valores)
{
if (x.Contains(cuentaDestino))
{
f_Script("alerta", "<script>alert('Cuenta a crear ya Existe.');window.location.href = 'RW_CuentasBancarias.aspx';</script>");
contador = 1;
}
}
if (contador == 1)
{
break;
}
}
if(contador != 1){
GuardaCuenta();
f_Script("alerta", "<script>alert('Su cuenta ha sido creada.');window.location.href = 'RW_Solicitud_Reembolso.aspx';</script>");
}

Seeing if a notepad contains the same word as the combo box has selected

So what my problem is and i have looked on the internet for this but really cannot find out how to do it.
I want to use my combo box which is populated with items from a notepad. i want the combo box to search through the notepad when an items from the combo box is selected and when it gets a match i want it to return the line number(ID).
This is what i thought would work, but it doesn't full work.
int items = File.ReadLines(#"C:\Users\PC\Documents\File\IDs.txt").Count();
string line;
int thisnum;
if (cboItemPick.SelectedIndex != -1)
{
if (cboItemPick.SelectedItem != null)
{
for (int i = 0; i <items;)
{
items = i;
line = File.ReadLines(#"C:\Users\PC\Documents\File\IDs.txt").ElementAt(items);
if (line == cboItemPick.Text)
{
MessageBox.Show("Boom");
break;
}
else
{
i++;
}
}
}
}

First of all, your code will have very bad performances. Please refer to this reviewed example:
if( cboItemPick.SelectedItem != null) {
var filepath = #"C:\Users\PC\Documents\File\IDs.txt";
var lines = File.ReadLines(filepath);
var keyword = cboItemPIck.SelectedItem as String;
for(var i = 0; i < lines.length; i++) {
var line = lines[i];
if( string.Compare(line, keyword) == 0) {
// Good, you have a match!
MessageBox.Show(string.Format("Item found at line: {0}", i));
break;
}
}
}
I hope this can help you.

You can try this:
var lines = File.ReadLines(#"C:\Users\PC\Documents\File\IDs.txt");
var result = lines.Select((i, index) => new { Value = i, Index = index }).ToList();
//Check if cboItemPick.SelectedItem is valid and set it to comboboxValue
var lineNumber = result.First(i => i.Value == comboboxValue).Select(i => i.Index);

Find a row in dataGridView based on column and value

I have a dataGridView that has 3 columns: SystemId, FirstName, LastName that is bound using database information. I would like to highlight a certain row, which I would do using:
dataGridView1.Rows[????].Selected = true;
The row ID I however do not know and the bindingsource keeps changing, thus row 10 could be "John Smith" in one instance but not even exist in another (I have a filter that filters out the source based on what user enters, so typing in "joh" would yield all rows where first / last name have "joh" in them, thus my list can go from 50 names to 3 in a click).
I want to find a way how I can select a row based on SystemId and a corresponding number. I can get the system ID using the following method:
systemId = dataGridView1.Rows[dataGridView1.CurrentRow.Index].Cells["SystemId"].Value.ToString();
Now I just need to apply it to the row selector. Something like dataGridView1.Columns["SystemId"].IndexOf(systemId} but that does not work (nor does such method exist). Any help is greatly appreciated.

This will give you the gridview row index for the value:
String searchValue = "somestring";
int rowIndex = -1;
foreach(DataGridViewRow row in DataGridView1.Rows)
{
if(row.Cells[1].Value.ToString().Equals(searchValue))
{
rowIndex = row.Index;
break;
}
}
Or a LINQ query
int rowIndex = -1;
DataGridViewRow row = dgv.Rows
.Cast<DataGridViewRow>()
.Where(r => r.Cells["SystemId"].Value.ToString().Equals(searchValue))
.First();
rowIndex = row.Index;
then you can do:
dataGridView1.Rows[rowIndex].Selected = true;

The above answers only work if AllowUserToAddRows is set to false. If that property is set to true, then you will get a NullReferenceException when the loop or Linq query tries to negotiate the new row. I've modified the two accepted answers above to handle AllowUserToAddRows = true.
Loop answer:
String searchValue = "somestring";
int rowIndex = -1;
foreach(DataGridViewRow row in DataGridView1.Rows)
{
if (row.Cells["SystemId"].Value != null) // Need to check for null if new row is exposed
{
if(row.Cells["SystemId"].Value.ToString().Equals(searchValue))
{
rowIndex = row.Index;
break;
}
}
}
LINQ answer:
int rowIndex = -1;
bool tempAllowUserToAddRows = dgv.AllowUserToAddRows;
dgv.AllowUserToAddRows = false; // Turn off or .Value below will throw null exception
DataGridViewRow row = dgv.Rows
.Cast<DataGridViewRow>()
.Where(r => r.Cells["SystemId"].Value.ToString().Equals(searchValue))
.First();
rowIndex = row.Index;
dgv.AllowUserToAddRows = tempAllowUserToAddRows;

Or you can use like this. This may be faster.
int iFindNo = 14;
int j = dataGridView1.Rows.Count-1;
int iRowIndex = -1;
for (int i = 0; i < Convert.ToInt32(dataGridView1.Rows.Count/2) +1; i++)
{
if (Convert.ToInt32(dataGridView1.Rows[i].Cells[0].Value) == iFindNo)
{
iRowIndex = i;
break;
}
if (Convert.ToInt32(dataGridView1.Rows[j].Cells[0].Value) == iFindNo)
{
iRowIndex = j;
break;
}
j--;
}
if (iRowIndex != -1)
MessageBox.Show("Index is " + iRowIndex.ToString());
else
MessageBox.Show("Index not found." );

Try this:
string searchValue = textBox3.Text;
int rowIndex = -1;
dataGridView1.SelectionMode = DataGridViewSelectionMode.FullRowSelect;
try
{
foreach (DataGridViewRow row in dataGridView1.Rows)
{
if (row.Cells["peseneli"].Value.ToString().Equals(searchValue))
{
rowIndex = row.Index;
dataGridView1.CurrentCell = dataGridView1.Rows[rowIndex].Cells[0];
dataGridView1.Rows[dataGridView1.CurrentCell.RowIndex].Selected = true;
break;
}
}
}
catch (Exception exc)
{
MessageBox.Show(exc.Message);
}

If you just want to check if that item exists:
IEnumerable<DataGridViewRow> rows = grdPdfs.Rows
.Cast<DataGridViewRow>()
.Where(r => r.Cells["SystemId"].Value.ToString().Equals(searchValue));
if (rows.Count() == 0)
{
// Not Found
}
else
{
// Found
}

This builds on the above answer from Gordon--not all of it is my original work.
What I did was add a more generic method to my static utility class.
public static int MatchingRowIndex(DataGridView dgv, string columnName, string searchValue)
{
int rowIndex = -1;
bool tempAllowUserToAddRows = dgv.AllowUserToAddRows;
dgv.AllowUserToAddRows = false; // Turn off or .Value below will throw null exception
if (dgv.Rows.Count > 0 && dgv.Columns.Count > 0 && dgv.Columns[columnName] != null)
{
DataGridViewRow row = dgv.Rows
.Cast<DataGridViewRow>()
.FirstOrDefault(r => r.Cells[columnName].Value.ToString().Equals(searchValue));
rowIndex = row.Index;
}
dgv.AllowUserToAddRows = tempAllowUserToAddRows;
return rowIndex;
}
Then in whatever form I want to use it, I call the method passing the DataGridView, column name and search value. For simplicity I am converting everything to strings for the search, though it would be easy enough to add overloads for specifying the data types.
private void UndeleteSectionInGrid(string sectionLetter)
{
int sectionRowIndex = UtilityMethods.MatchingRowIndex(dgvSections, "SectionLetter", sectionLetter);
dgvSections.Rows[sectionRowIndex].Cells["DeleteSection"].Value = false;
}

Those who use WPF
for (int i = 0; i < dataGridName.Items.Count; i++)
{
string cellValue= ((DataRowView)dataGridName.Items[i]).Row["columnName"].ToString();
if (cellValue.Equals("Search_string")) // check the search_string is present in the row of ColumnName
{
object item = dataGridName.Items[i];
dataGridName.SelectedItem = item; // selecting the row of dataGridName
dataGridName.ScrollIntoView(item);
break;
}
}
if you want to get the selected row items after this, the follwing code snippet is helpful
DataRowView drv = dataGridName.SelectedItem as DataRowView;
DataRow dr = drv.Row;
string item1= Convert.ToString(dr.ItemArray[0]);// get the first column value from selected row
string item2= Convert.ToString(dr.ItemArray[1]);// get the second column value from selected row

string text = "param";
var rows = dataGridViewlist.Rows.OfType<DataGridViewRow>()
.Select(x => new { Value = x.Cells[6].Value.ToString(), Index = x.Index }).ToList();
var index= rows.Where(w => w.Value == text).Select(s => s.Index).FirstOrDefault();

You can try:
string DT = string.Empty;
try
{
DT = $"{dataGridView1.SelectedRows[0].Cells[1].Value}-{dataGridView1.SelectedRows[0].Cells[2].Value}-{dataGridView1.SelectedRows[0].Cells[3].Value}-{dataGridView1.SelectedRows[0].Cells[4].Value}";
}
catch { }
try
{
dataGridView1.Rows.Cast<DataGridViewRow>().Where(x => $"{x.Cells[1].Value}-{x.Cells[2].Value}-{x.Cells[3].Value}-{x.Cells[4].Value}" == DT).ToList()[0].Selected = true;
}
catch (Exception ex) { }