Why does my Unity script not work properly?-CodePudding

I was trying to implement a moving system but there is an error that I don’t know what it means:

Assets\moving_BEAN.cs(14,52): error CS1526: A new expression requires (), [], or {} after type

This is my code:

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class moving_BEAN : MonoBehaviour
{
    public float speed;

    void Update()
    {
        float h = Input.GetAxisRaw("Horizontal");
        float v = Input.getAxisRaw("Vertical");

        gameObject.transform.position = new vector2;

        transform.position.x   (h*speed);
        transform.position.y  (v * speed);
    }
}

CodePudding user response：

First of all transform.position is a Vector3, You don't overwrite that to a Vector3. Second, if You give a value to a variable like that, You close the new ClassName with (), so it looks like this: Classname varname = new Classname(). Third, please provide more information regarding your problem. I cannot decide if this is a Unity3D project or 2D. Fourth, You don't use things like this:

transform.position.x   (h*speed);
transform.position.y  (v * speed);

You use =:

transform.position.x  = (h*speed);
transform.position.y  = (v * speed);

And these 2 line are enough. You don't need the one line it gives the error.

Also, since you move the BEAN in an Update() method, which is frame-dependant, you should consider doing the following:

transform.position.x  = (h * speed * Time.deltaTime);
transform.position.y  = (v * speed * Time.deltaTime);

This way the bean will move consistently, not depending on the framerate.

CodePudding user response：

There’s a “syntax” error, and a usage error (or two depending on how you count it).

First, the syntax error is that you’ve missed the parentheses after creating a new struct.

BUT, for your use case, you probably don’t want to be doing this. What would make more sense is to get a copy of the transform’s current position, perform the calculations on that copy, before assigning the whole value back to the transform.position field.

var pos = transform.position;
pos.x  = h * speed * Time.deltaTime;
pos.y  = v * speed * Time.deltaTime;
transform.position = pos;

Notice I also modified the position changes by Time.deltaTime so as to account for the frame rate.

The reason we have to work on a new copy of the position value is because position is a struct which is a “value” type. This is in contrast to a “reference” type, which you wouldn’t need to do this with.

CodePudding user response：

Here, on line 14, do this to fix it

gameObject.transform.position = new Vector2();

Does your IDE give you red sqwiggly line? You can click the error to go up to that line.