If Then Blocks

if / else blocks are a way for your robot to make decisions during a project.

Understanding if / else blocks

The if then branch

An if/else block has two parts. In the if then branch, you insert a Boolean block into the condition slot for the robot to check, and add the blocks you want to run when the condition is true.

The else branch

In the else branch, you add the blocks you want to run when the condition is false.

Insert a Boolean block

Drag a Boolean block into the empty condition slot in the if then branch.

All Boolean blocks have sharp edges and a question mark in its name, such as the controller button pressed? block.

If the condition is true

If the condition is true, the blocks inside the if then branch will run.

If the condition is false

If the condition is false, the blocks inside the else branch will run.

Repeating if / else blocks

An if/else block only checks its condition once. If you want the condition to be checked repeatedly, put the if/else block inside a looping block, like forever.

An if/else block nested inside a forever block.

永久循环
如果 <Controller [R ▲ v] 按下了？> 那么
驱动 [向前 v]
否则
驱动停止
结束
结束

The if Block

The if block is only the if then branch. If the condition isn’t true, nothing will happen.

The if block.

如果 <Controller [R ▲ v] 按下了？> 那么
驱动 [向前 v]
结束

The if / else if / else Block

The if / else if / else block can be used to test multiple conditions one after another. It can be expanded to test as many conditions as needed.

An if/else if/else block, testing all three Brain buttons.

如果 <Brain [◀ v] 键按下了？> 那么
[左 v] 转 (90) 度 ▶
否则如果 <Brain [▶ v] 键按下了？> 那么
[右 v] 转 (90) 度 ▶
否则如果 <Brain [确认 v] 键按下了？> 那么
驱动停止
否则
驱动 [向前 v]
结束