javascript - 如何仅更改对象的一个​​属性

Question

我正在构造一个对象，并且只有一个属性应该根据另一个值进行更改，因此开关是理想的选择，但我不能将开关放在对象的初始化中。我知道这可能相当简单，但我是 JS 新手。

class DegreesCircle extends React.Component {
    constructor(props) {
        super(props);

        this.state = {
            type: this.props.type,
            degrees: this.props.degrees
        }
    }

    render() {
        let circleStyle = {
            position: "relative",
            left: "50%",
            top: "45%",
            transform: "translate(-50%, 0)",

            //I need this to change according to this.props.type
            //I'd put a switch in here if I could
            borderColor: "a value",
            borderStyle: "solid",
            borderWidth: "0.5vh",
            borderRadius: "50%",
            width: "20vh",
            height: "20vh",
        }

如何仅更改 CircleStyle 的 borderColor 属性？

编辑:我不想把开关放在前面什么的。我正在考虑更改对象的一个​​属性。

Answer 1

您可以使用扩展语法

 let circleStyle = {
        position: "relative",
        left: "50%",
        top: "45%",
        transform: "translate(-50%, 0)",
        borderStyle: "solid",
        borderWidth: "0.5vh",
        borderRadius: "50%",
        width: "20vh",
        height: "20vh",
    }


switch (this.props.type) {
case x: 
  circleStyle = {
      ...circleStyle,
      borderColor: value,
  }
  break;
case y:
  ....