GameObject.GetComponent

返回

T A reference to a component of the type T if one is found, otherwise null.

描述

Gets a reference to a component of type T on the specified GameObject.

The typical usage for this method is to call it on a reference to a different GameObject than the one your script is on. For example:

myResults = otherGameObject.GetComponent<ComponentType>()

However if you are writing code inside a MonoBehaviour class, you can omit the preceding GameObject reference to get a component from the same GameObject your script is attached to. In this instance, you are actually calling Component.GetComponent because the script itself is a type of component, but the result is the same as if you had referenced the GameObject itself. For example:

myResults = GetComponent<ComponentType>()

GetComponent returns only the first matching component found on the GameObject on which it is called, and the order that the components are checked is not defined. Therefore, if there are more than one of the specified type that could match, and you need to find a specific one, you should use Component.GetComponents and check the list of components returned to identify the one you want.

To find components attached to other GameObjects, you need a reference to that other GameObject (or any component attached to that GameObject). You can then call GetComponent on that reference.

See the Component and GameObject class reference pages for the other variations of the GetComponent family of methods.

The following example gets a reference to a hinge joint component on the referenced GameObject, and if found, sets a property on that hinge joint component.

using UnityEngine;

public class GetComponentExample : MonoBehaviour
{
    public GameObject otherGameObject;

    void Start()
    {
        HingeJoint hinge = otherGameObject.GetComponent<HingeJoint>();

        if (hinge != null)
        {
            hinge.useSpring = false;
        }
    }
}

Note: If the type you request is a derivative of MonoBehaviour and the associated script can't be loaded then this function will return `null` for that component.

参数

返回

Component A Component of the matching type, otherwise null if no Component is found.

描述

The non-generic version of this method.

This version of GetComponent is not as efficient as the Generic version (above), so you should only use it if necessary.

using UnityEngine;

public class GetComponentExample : MonoBehaviour
{
    public GameObject otherGameObject;

    void Start()
    {
        HingeJoint hinge = otherGameObject;.GetComponent(typeof(HingeJoint)) as HingeJoint;

        if (hinge != null)
        {
            hinge.useSpring = false;
        }
    }
}

参数

返回

Component A Component of the matching type, otherwise null if no Component is found.

描述

The string-based version of this method.

This version of GetComponent is not as efficient as the Generic version (above), so you should only use it if necessary.

using UnityEngine;

public class GetComponentNonPerformantExample : MonoBehaviour
{
    public GameObject otherGameObject;

    void Start()
    {
        HingeJoint hinge = otherGameObject.GetComponent("HingeJoint") as HingeJoint;

        if (hinge != null)
        {
            hinge.useSpring = false;
        }
    }
}