index was out of range

suhel jamadar

5y899Windows Forms

index was out of range must be nonnegative and less than the size of the collection parameter index

3 Replies

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Mageshwaran R5y ago
Hi Suhel,
Try this code:
List<string> temp = new List<string>();
temp[0] = lines[0];
temp[1] = lines[1];
temp.Add(lines[0]);
temp.Add(lines[1]);
Rajanikant Hawaldar5y ago
Hello Suhel, its self explanatory you could have fix it yourself i am giving one example, Lets consider below code when trying to add data as one by one row to a datagridview will get this error runtime.
String Sqlstr2 = "select ItemName from Item where ItemID = '" + tbItemID.Text + "'";
db.DataRead(Sqlstr2);
string ItemName = db.dr["ItemName"].ToString();

DataGridView dataGridView1 = new DataGridView();

dataGridView1.Columns[0].Name = "ItemID";
dataGridView1.Columns[1].Name = "ItemName";
dataGridView1.Columns[2].Name = "Qty";
dataGridView1.Columns[3].Name = "UnitPrice";
dataGridView1.Columns[4].Name = "Amount";

string firstColum = tbItemID.Text;
string secondColum = ItemName;
string thirdColum = tbQuantity.Text;
string fourthColum = Convert.ToString(UnitPrice);
string fifthColum = Convert.ToString(sum);

string[] row = new string[]{ firstColum, secondColum, thirdColum, fourthColum, fifthColum };
dataGridView1.Rows.Add(row);
Fix is to add columns
dataGridView1.ColumnCount = 5;
before below line of code
dataGridView1.Columns[0].Name = "ItemID";
Sachin Singh5y ago
it means you are assigning something that doesn't even exist.
for example in your database there is 100 rows and in your checkboxList there is 4 item and you are looping through database table and trying to match checkboxlist text with it , so it out of range.
reverese the process loop through checkboxList and match database table columns , now you won't get any error.

so to avoid this remember one thing always loop through the collection which has less items and under that compare items which has more items.