控制

介绍

Control in Python lets you tell the robot when to wait, when to repeat actions, how to make decisions, and when end the project.

以下是可用控件列表，包括方法和核心 Python 关键字：

• wait – Pauses the project for a given time.

• for – Repeats code for each item in a sequence.

• if – Runs code if a condition is true.

• if/else – Runs different code depending on a condition.

• if/elif/else – Checks multiple conditions in order.

• while – Repeats code while a condition is true.

• break – Exits a loop immediately.

• stop_program – Ends the running program.

• pass – Placeholder used when no action is needed.

等待

wait pauses for a specific amount of time before moving to the next line of code.

用法：
wait(time, units)

参数	描述
time	The amount of time to wait, as a positive whole number or decimal.
units	The unit that represents the wait time: MSEC (default) – milliseconds, or SECONDS

# Build Used: Super Code Base 2.0
def main():
    # Turn right for one second
    drivetrain.turn(RIGHT)
    wait(1, SECONDS)
    drivetrain.stop()

# Start threads — Do not delete
start_thread(main)

为了

for repeats a set of actions a specific number of times. for can be used to loop through items in lists, tuples, dictionaries, sets, strings, or for a specified amount of loops with range.

使用量：

for value in expression_list:
    pass

成分	描述
value	存储迭代中的当前元素的临时变量。
expression_list	循环遍历的元素集合（例如，列表、字符串、范围）。

# Build Used: Super Code Base 2.0
def main():
    # Move in a square path
    for index in range(4):
        drivetrain.drive_for(FORWARD, 100, MM)
        drivetrain.turn_for(RIGHT, 90)

# Start threads — Do not delete
start_thread(main)

如果

if runs the indented block of code if the condition is True.

用法：

if condition:
    pass

成分	描述
condition	An expression or variable that is checked when the statement runs. If it is True, the code inside the if block executes; if it is False, the block is skipped.

# Build Used: Super Code Base 2.0
def main():
    # Turn when the bumper is pressed
    while True:
        if bumper.is_pressed():
            drivetrain.turn_for(RIGHT, 90)
        wait(0.1, SECONDS)

# Start threads — Do not delete
start_thread(main)

如果/否则

if and else determine which indented block of code runs based on whether the condition is True or False.

用法：

if condition:
    pass
else:
    pass

成分	描述
condition	An expression or variable that is checked when the statement runs. If it is True, the code inside the if block executes; if it is False, the code inside the else block executes instead.

# Build Used: Super Code Base 2.0
def main():
    # Turn when the bumper is pressed
    while True:
        if bumper.is_pressed():
            drivetrain.turn(RIGHT)
        else:
            drivetrain.stop()
        wait(0.1, SECONDS)

# Start threads — Do not delete
start_thread(main)

如果/否则

if/elif/else 结构根据条件选择运行哪个缩进的代码块：

• if runs its block if the condition is True.

• elif checks additional conditions only if all previous conditions are False. Multiple elif statements can be used.

• else runs its block only if none of the previous conditions are True.

用法：

if condition:
    pass
elif condition:
    pass
else:
    pass

成分	描述
condition	An expression or variable that is checked when the statement runs. The first condition that is True determines which block executes; if none are True, the else block runs.

# Build Used: Super Code Base 2.0
def main():
    # Change the LED while turning
    drivetrain.turn(RIGHT)
    while True:
        if drivetrain.get_heading() < 120:
            bumper.set_color(OFF)
        elif drivetrain.get_heading() < 240:
            bumper.set_color(RED)
        else:
            bumper.set_color(GREEN)
        wait(0.2, SECONDS)

# Start threads — Do not delete
start_thread(main)

尽管

while repeatedly runs code as long as the condition is True. It can also be used like a “forever” by using True as the condition, or a “wait until” by adding not to the condition, as shown in the examples below.

用法：

while condition:
    pass

成分	描述
condition	An expression or variable that is checked before each iteration. If it is True, the loop continues; if it is False, the loop stops.

# Build Used: Super Code Base 2.0
def main():
    # Turn when the bumper is pressed
    while True:
        if bumper.is_pressed():
            drivetrain.turn(RIGHT)
        else:
            drivetrain.stop()
        wait(0.1, SECONDS)

# Start threads — Do not delete
start_thread(main)

# Build Used: Super Code Base 2.0
def main():
    # Turn the other direction when the bumper is pressed
    drivetrain.turn(LEFT)
    while not bumper.is_pressed():
        wait(0.2, SECONDS)
    drivetrain.turn(RIGHT)

# Start threads — Do not delete
start_thread(main)

休息

break exits a loop immediately. break can be used to leave loops that otherwise would loop forever.

使用量：

break

参数	描述
	此关键字没有参数。

# Build Used: Super Code Base 2.0
def main():
    # Stop turning after pressing the bumper
    while True:
        drivetrain.turn(RIGHT)
        if bumper.is_pressed():
            break
        wait(0.2, SECONDS)
    drivetrain.stop()
    bumper.set_color(RED)

# Start threads — Do not delete
start_thread(main)

停止程序

stop_program ends a running project.

Usage:
stop_program()

参数	描述
	该方法没有参数。

# Build Used: Super Code Base 2.0
def main():
    # Stop the project after pressing the bumper
    while True:
        drivetrain.turn(RIGHT)
        if bumper.is_pressed():
            break
        wait(0.2, SECONDS)
    stop_program()

# Start threads — Do not delete
start_thread(main)

经过

pass 是未来代码的占位符，可用于避免空循环、条件和函数中的错误。

使用量：

pass

参数	描述
	此关键字没有参数。

if condition:
    pass

def function():
    pass