声明之前无法使用局部变量“ hitInfo”

Question

将项目更新为最新版本的unity3d后，出现此错误 “错误CS0841：在声明它之前无法使用局部变量'hitInfo' “

if (Physics.Linecast(head.position, vector, out hitInfo, sphereSensor.obstacleLayer) && Physics.Linecast(head.position, vector2, out hitInfo, sphereSensor.obstacleLayer) && Physics.Linecast(head.position, colliderTarget.bounds.center, out RaycastHit hitInfo, sphereSensor.obstacleLayer))

代码有什么问题？

Answer 1

您必须在条件中更早声明（Type variableName，因为它们是从左到右求值的，然后在第一个条件（Physics.Linecast(head.position, vector, out hitInfo, sphereSensor.obstacleLayer)）中，变量hitInfo不声明还不存在。

将代码更改为此：

// Notice this ---------------------------------v--------v
if (Physics.Linecast(head.position, vector, out RaycastHit hitInfo, sphereSensor.obstacleLayer)
 && Physics.Linecast(head.position, vector2, out hitInfo, sphereSensor.obstacleLayer)
 && Physics.Linecast(head.position, colliderTarget.bounds.center, out hitInfo, sphereSensor.obstacleLayer))
// Type was removed there -------------------------------------------^

或在之前声明变量：

RaycastHit hitInfo;

if (Physics.Linecast(head.position, vector, out hitInfo, sphereSensor.obstacleLayer)
 && Physics.Linecast(head.position, vector2, out hitInfo, sphereSensor.obstacleLayer)
 && Physics.Linecast(head.position, colliderTarget.bounds.center, out hitInfo, sphereSensor.obstacleLayer))