How to negotiate ICAP_FRAMES

The process of negotiating ICAP_FRAMES is the same as all the other capabilities. However, Frame has 4 data members: Left, Top, Right and Bottom, which can not be held in CapValue or CapValueString properties. Dynamic TWAIN provides several methods to deal with Frame: CapGetFrameLeft(), CapGetFrameTop(), CapGetFrameRight(), CapGetFrameBottom() and CapSetFrame().

For the general steps of capability negotiation, please refer to How to Negotiate Capability with Different Capability Container Types. 

The followings are the samples of ICAP_FRAMES negotiation:

Getting frame information;

Setting one frame;

Setting multiple frames.

Getting frame information

C# Sample: 
    
		int lngIndex  = 0;
		string strFrame;
		
		Twain.OpenSource();
		
		Twain.Capability = Dynamsoft.DotNet.TWAIN.Enums.TWCapability.ICAP_FRAMES;
		
		if (!Twain.CapGet())
		{
			MessageBox.Show("Failed.\r\n" + Twain.ErrorString);
			return;
		}
		
		if (Twain.CapType == Dynamsoft.DotNet.TWAIN.Enums.TWCapType.TWON_ONEVALUE)
		{
			strFrame = "Frame left: " + Twain.CapGetFrameLeft(0) + "\r\n";
			strFrame = strFrame + "Frame top: " + Twain.CapGetFrameTop(0) + "\r\n";
			strFrame = strFrame + "Frame right: " + Twain.CapGetFrameRight(0) + "\r\n";
			strFrame = strFrame + "Frame bottom: " + Twain.CapGetFrameBottom(0);
			
			MessageBox.Show(strFrame);
		}
		else if (Twain.CapType == Dynamsoft.DotNet.TWAIN.Enums.TWCapType.TWON_ENUMERATION)
		{
			for (lngIndex = 0; lngIndex < Twain.CapNumItems; lngIndex++)
			{
				strFrame = "Frame left: " + Twain.CapGetFrameLeft(lngIndex) + "\r\n";
				strFrame = strFrame + "Frame top: " + Twain.CapGetFrameTop(lngIndex) + "\r\n";
				strFrame = strFrame + "Frame right: " + Twain.CapGetFrameRight(lngIndex) + "\r\n";
				strFrame = strFrame + "Frame bottom: " + Twain.CapGetFrameBottom(lngIndex);
				
				MessageBox.Show(strFrame);
			}
		}

Setting one frame

C# Sample: 
		Twain.OpenSource();
					
		Twain.Capability = Dynamsoft.DotNet.TWAIN.Enums.TWCapability.ICAP_FRAMES;
		
		Twain.CapType = Dynamsoft.DotNet.TWAIN.Enums.TWCapType.TWON_ONEVALUE;
		
		Twain.CapSetFrame(0, 0, 0, 5, 5);
		
		if (Twain.CapSet())
			MessageBox.Show("Successful.");
		else
			MessageBox.Show("Failed.\r\n" + Twain.ErrorString);

Setting multiple frames

C# Sample: 
		Twain.OpenSource();
		
		Twain.Capability = Dynamsoft.DotNet.TWAIN.Enums.TWCapability.ICAP_FRAMES;
		
		Twain.CapType = Dynamsoft.DotNet.TWAIN.Enums.TWCapType.TWON_ENUMERATION;
		
		Twain.CapNumItems = 2;
		Twain.CapSetFrame(0, 0, 0, 5, 5);
		Twain.CapSetFrame(1, 6, 6, 8, 8);
		
		if (Twain.CapSet())
			MessageBox.Show("Successful.");
		else
			MessageBox.Show("Failed.\r\n" + Twain.ErrorString);