Hi,
at our project we have specific request on search feature in datagridview. When user starts typing in datagrid we have to perform incremental search in selected column (in THE column that is sorted) as user types. At the same time the grid should scroll through records the datagrid. I know the similar functionality in that use case is achieved via filter, but customer want to have all the items in the grid while searching for the record.

is there any easier way to implement this than i mention lower?

It's just a first draft because i will have to extend this code so that typed string is somehow "visible" to the user)

The GetSortedColumnIX just returns index of the column that is sorted.

Hi Kalaz.Net,

You can use binary search to speed up searching. This is the code snippet:
//Search class, assume the sort type is ascending.

public static class QuickSearch

{

public static int Search(DataGridView grid, int sortedColumnIndex, string startString)

{

int start = 0;

int end = grid.Rows.Count - 1;

return Search(grid, sortedColumnIndex, startString, start, end);

}

private static int Search(DataGridView grid, int sortedColumnIndex, string startString, int start, int end)

{

//Not found

if (string.IsNullOrEmpty(startString) || start > end) return -1;

//Get the string of the middle cell.

int midPos = (start + end) / 2;

object cellVal = grid[sortedColumnIndex, midPos].Value;

string cellString = cellVal == null ? "" : cellVal.ToString().Trim();

//Handle start == end

if (start == end)

return cellString.StartsWith(startString) ? start : -1;

//Handle blank.

if(cellString == "")

{

if(start < end)

{

//Search in the follow items.

return Search(grid,sortedColumnIndex,startString,start + 1, end);

}

else

return -1;//Not found.

}

if (cellString.Length >= startString.Length)

{

cellString = cellString.Substring(0, startString.Length);

int diff = cellString.CompareTo(startString);

if (diff == 0)

return midPos;//This means cellString starts with startString.

else if (diff > 0)

//cellString > startString, search in the first half.

return Search(grid, sortedColumnIndex, startString, start, midPos - 1);

else

//cellString < startString, search in the last half.

return Search(grid, sortedColumnIndex, startString, midPos + 1, end);

}

else

{

string newStartString = startString.Substring(0, cellString.Length);

int diff = newStartString.CompareTo(cellString);

if (diff >= 0)

//startString > cellString, search in the last half.

return Search(grid, sortedColumnIndex, startString, midPos + 1, end);

else

//startString < cellString, search in the first half.

return Search(grid, sortedColumnIndex, startString, start, midPos - 1);

}

}

}

Let me know if this helps.
Aland Li

---

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Hi Kalaz.Net,

You can use binary search to speed up searching. This is the code snippet:
//Search class, assume the sort type is ascending.

public static class QuickSearch

{

public static int Search(DataGridView grid, int sortedColumnIndex, string startString)

{

int start = 0;

int end = grid.Rows.Count - 1;

return Search(grid, sortedColumnIndex, startString, start, end);

}

private static int Search(DataGridView grid, int sortedColumnIndex, string startString, int start, int end)

{

//Not found

if (string.IsNullOrEmpty(startString) || start > end) return -1;

//Get the string of the middle cell.

int midPos = (start + end) / 2;

object cellVal = grid[sortedColumnIndex, midPos].Value;

string cellString = cellVal == null ? "" : cellVal.ToString().Trim();

//Handle start == end

if (start == end)

return cellString.StartsWith(startString) ? start : -1;

//Handle blank.

if(cellString == "")

{

if(start < end)

{

//Search in the follow items.

return Search(grid,sortedColumnIndex,startString,start + 1, end);

}

else

return -1;//Not found.

}

if (cellString.Length >= startString.Length)

{

cellString = cellString.Substring(0, startString.Length);

int diff = cellString.CompareTo(startString);

if (diff == 0)

return midPos;//This means cellString starts with startString.

else if (diff > 0)

//cellString > startString, search in the first half.

return Search(grid, sortedColumnIndex, startString, start, midPos - 1);

else

//cellString < startString, search in the last half.

return Search(grid, sortedColumnIndex, startString, midPos + 1, end);

}

else

{

string newStartString = startString.Substring(0, cellString.Length);

int diff = newStartString.CompareTo(cellString);

if (diff >= 0)

//startString > cellString, search in the last half.

return Search(grid, sortedColumnIndex, startString, midPos + 1, end);

else

//startString < cellString, search in the first half.

return Search(grid, sortedColumnIndex, startString, start, midPos - 1);

}

}

}

Let me know if this helps.
Aland Li

---

Please mark the replies as answers if they help and unmark if they don't. This can be beneficial to other community members reading the thread.

Hi Kalaz.Net,

Please let me know if my code snippet helps. Based on my understanding, you want to find the row faster. Please feel free to tell me if I misunderstand you.

You said is there any easier way to implement this than i mention lower? Do you mean you want to simplify the code?

Best regards,
Aland Li

---

Please mark the replies as answers if they help and unmark if they don't. This can be beneficial to other community members reading the thread.

Hi,

We are changing the issue type to “General Discussion�because you have not followed up with the necessary information. If you have more time to look at the issue and provide more information, please feel free to change the issue type back to “Question�by opening the Options list at the top of the post window, and changing the type. If the issue is resolved, we will appreciate it if you can share the solution so that the answer can be found and used by other community members having similar questions.

Best regards,
Aland Li

---

Please mark the replies as answers if they help and unmark if they don't. This can be beneficial to other community members reading the thread.

I am sorry, I haven't had time up until now to report back. Your solution is good but i have to make a few adjustments, i will post back when it's ready.