AutoCAD uses commands and system variables

                  This tutorial is designed to introduce AutoCAD usage commands and system variables to students who are new to cad. Let's take a look at it.

In AutoCAD, menu commands, tool buttons, commands, and system variables mostly correspond to each other. You can select a menu command, or click a tool button, or enter commands and system variables on the command line to execute the command. It can be said that the command is the core of AutoCAD drawing and editing graphics.

1. Execute the command using the mouse operation

2. Use the command line

3. Use the transparent command

4. Use the system variable

1. Execute the command with the mouse operation

In the drawing window, the cursor is usually displayed in the form of “10”. When the cursor moves into a menu option, tool, or dialog, it turns into an arrow. Whether the cursor is in the form of "10" or "arrow", when the mouse button is clicked or pressed, the corresponding command or action is executed. In AutoCAD, mouse buttons are defined according to the rules below.

Pickup Key: Usually refers to the left mouse button, which is used to specify points on the screen, and can also be used to select Windows objects, AutoCAD objects, toolbar buttons, menu commands, and so on.

Enter key: refers to the right mouse button, which is equivalent to the Enter key. It is used to end the currently used command. At this time, the system will pop up different shortcut menus according to the current drawing state.

Pop-up menu: When using the combination of Shift and right mouse button, a shortcut menu will pop up to set the method for capturing points. For a 3-button mouse, the eject button is usually the middle button of the mouse.

2, using the command line

In AutoCAD 2007, by default, "command line" is a fixed window, you can enter commands, object parameters at the current command prompt And so on. For most commands, "command line" can display two command prompts (also called command history), and for some output commands, such as TIME and LIST commands, you need to zoom in on the "command line". Or in the "AutoCAD text window" in order to be fully displayed.

Right-click in the "command line" window and AutoCAD will display a shortcut menu. It allows you to select the 6 most recently used commands, copy selected text or all command history, paste text, and open the “Options” dialog.

In the command line, you can also use the BackSpace or Delete key to delete the text in the command line; you can also select the command history and execute “ paste to the command line & rdquo; command, paste it into the command line .

3, using transparent commands

In AutoCAD, transparent commands are commands that can be executed during the execution of other commands. Often used transparent commands are commands to modify graphics settings, drawing aids commands such as SNAP, GRID, ZOOM, etc.

To use commands transparently, enter single quotation marks (') before entering the command. On the command line, there is a double apostrophe (>>) before the prompt for the transparent command. After the transparent command is completed, the original command will continue.

4, Using System Variables

In AutoCAD, system variables are used to control certain functions and design environments, how commands work, and can turn snaps, rasters, or orthogonals on or off. Wait for the drawing mode, set the default fill pattern, or store information about the current drawing and AutoCAD configuration.

System variables are usually abbreviated names of 6 to 10 characters long. Many system variables have simple switch settings. For example, the GRIDMODE system variable is used to display or close the grid. When you enter 0 at the new value of the input GRIDMODE at the command line, you can turn off the grid display; when you enter 1, you can open the grid. The grid is displayed. Some system variables are used to store values ​​or literals, such as the DATE system variable to store the current date.

You can modify system variables in the dialog box, or you can modify system variables directly on the command line. For example, to modify the wireframe density of a surface using the ISOLINES system variable, enter the system variable name at the command prompt and press Enter, then enter the new system variable value and press Enter. The details are as follows.

Command: ISOLINES (enter system variable name)

Enter the new value for ISOLINES <4>: 32 (enter the new value of the system variable)