This feature option is currently available in autocad2010 and needs to be checked at the time of installation.
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If it is not installed, you can reinstall the Toolkit from the Control Panel-Add and Remove Programs, and some commands will be useful.
Starting with AutoCADR14 Autodesk has added a program based on AutoCAD, the extension tool. AUTOCADR14 is called the "bonus program", the English version of "BONUS", AutoCAD2002 and later versions are called "et extension tool", the English version of "Expresstools". When working with AutoCAD, you can take advantage of AutoCAD's inherent commands to perform a series of drawing operations. But sometimes, always feel that some of the commands in use, must be required to make multiple choices, only to start the execution, once, two times nothing, command with a lot of feeling very troublesome, to improve the speed of the drawing is also an obstacle. As a result, many CAD experts in accordance with their own drawing requirements, environment, habits, etc., to CAD two times to develop, do a lot of "plug-ins", "Tools", "external" and other practical extension tools. In fact, AutoCAD itself with this kind of practical extension tool "et extension tool", there are many useful tools to help you do layer management, writing, pixel editing, drawing assistance, super fill pattern, size style, etc., after installation, They will appear in your AutoCAD menu in a regular manner. Various versions of the "ET extension tool" features are not necessarily the same, but similar, as long as a few familiar, can be skilled use, you will have a powerful feeling, greatly improve your drawing speed, will be just about the corner.
The main commands and their functions of the ET extension tool
LMAN: Write layer contents to file or load file
LAYMCH: Click Reference object to change the drawing layer
Laycur: Click on an object to change the layer to the current layer
Layiso: Click object to display the rest of the layer close
LAYFRZ: Click object to freeze the layer
Layoff: Click object to close the layer
Laylck: Click object to lock the layer
Layulk: Click an object to unlock the layer
Layon: Open all layers that are closed
LAYTHW: unfreeze All frozen layers
Textfit: Re-adjust the text as fit (fill in)
Textmask: Temporary elimination of overlapping objects at text
CHT: Modifying the properties of multiple text
Txtexp: Breaking text into line objects
Arctext: Writes text on a clicked arc segment
Find: Find and replace text content
BURST: Convert block word to general text
Gatte: Modifying block attribute text content
Exchprop: Modifying the properties of an object
Mstretch: Multi-marquee for stretch (stretch)
Mocoro: Synchronous Move copy rotation scale adjustment
Extrim: Click the enclosing object for one cut
CLIPLT: Click on any object for local interception
Mpedit: Multi-Object Click for Edit
Xplode: Decomposing objects and specifying the attributes after decomposition
NCOPY: Single-click Objects for replication
Btrim: You can click Block to cut the boundary
Bextend: You can click Biock to extend the boundary
Wipeout: Creating an eraser
Revcloud: An arc-length freehand drawing spline
Gqlattach: Link leads are associated with Mtext
Qldetachset: Separating the relationship between the leader and the text
PACK: Copy diagram files and related files used
GetSel: Calculating the number of layers or categories of objects
xl1st: Query block, xref internal files
XDATA: Creating an extension file
Xdlist: Query extension file
Dimex: Write a dimension style out of a file
Dimim: Reading a dimension style file into
Fullscreen: Extending the scope of the AutoCAD graphics window
Laydel: Delete all objects of the specified layer
LAYMRG: Moves all objects of the specified layer to another layer and deletes the specified layer at the same time
Mkltype: Click a line, polyline, or text composition style to convert to a linetype
Pljoin: A number of non-dense polylines, specifying a distance, combined into one
Rtext: Use OLE features to quickly embed text objects in a drawing
Rtedit: Modifying Rtext Object-related properties
Superhatch: Use tiles, images, external references, and wipeouts to create pattern patterns for fill patterns
Txt2mtxt: Converts a Text object dtext or text command to a multi-line text Mtext object http://blog.sina.com.cn/s/blog_567bc42a010172d0.html-