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Javascript 如何在此数组中添加所有值?它';每次创建一个新的客户机阵列并向其推送值时_Javascript_Arrays_Reactjs - Fatal编程技术网

Javascript 如何在此数组中添加所有值?它';每次创建一个新的客户机阵列并向其推送值时

Javascript 如何在此数组中添加所有值?它';每次创建一个新的客户机阵列并向其推送值时,javascript,arrays,reactjs,Javascript,Arrays,Reactjs,如何将当前值添加到以前的值,而不是替换它们 将值添加到CLIENT=[value1,value2]后,我希望它是CLIENT=[value1,value2,value3]您需要将以前的客户端状态合并或扩展到新状态: this.state = { CLIENT: [] } handleChange = (event) => { const value = event.target.value; this.setState({ CLIENT: [value] });

如何将当前值添加到以前的值,而不是替换它们


将值添加到
CLIENT=[value1,value2]
后,我希望它是
CLIENT=[value1,value2,value3]
您需要将以前的客户端状态合并或扩展到新状态:

this.state = {
  CLIENT: []
}

handleChange = (event) => {
  const value = event.target.value;
  this.setState({
    CLIENT: [value]
  });
};
handleChange = (event) => {
  const value = event.target.value;
  this.setState(prevState => ({
    CLIENT: [...prevState.CLIENT, value]
  }));
};