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Showing posts from June, 2007

Image-Based Bot Detector

Image-Based Bot Detector is a variant of image-based CAPTCHAs that uses human ability to recognize a distorted region on the image he never seen before.

Licence Copyright (c) 2007, Mykola Tarasyuk
All rights reserved.
Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:
* Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
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* The name of the copyright holder may not be used to endorse or promote products derived from this software without specific prior written permission.

THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTA…

Merging columns in GridView/DataGrid header

As necessity to show header columns in a few rows occurs fairly often it would be good to have such functionality in the GridView/DataGrid control as an in-built feature. But meanwhile everyone solves this problem in his own way.

The described below variant of the merging implementation is based on irwansyah's idea to use the SetRenderMethodDelegate method for custom rendering of grid columns header. I guess this approach can be simplified in order to get more compact and handy code for reuse.
The code overview
As it may be required to merge a few groups of columns - for example, 1,2 and 4,5,6 - we need a class to store common information about all united columns.
[Serializable]
private class MergedColumnsInfo
{
// indexes of merged columns
public List<int> MergedColumns = new List<int>();
// key-value pairs: key = the first column index, value = number of the merged columns
public Hashtable StartColumns = new Hashtable();
// key-value pairs: key = the first column in…