react setState 状态更改

Question

  addEditChange(e,key){

        let that = this;

        let add_edit_form = that.state.add_edit_form;

            add_edit_form[key] = e.target.value;

        that.setState({

            add_edit_form:add_edit_form

        })

        console.log(that.state.budget_form);

    }

    

    

    我 setState  add_edit_form  为啥budget_form里面的值也会变

    

Answer 1

典型的shallow copy跟deep copy（某个地方add_edit_form 等于 budget_form了）， 你要改变的话最好用import update from 'react-addons-update';...const add_edit_form = update(budget_form, {a: {$set: 'b'}})//或者更新自己const add_edit_form = update(this.state.add_edit_form, {a: {$set: 'b'}})//新的add_edit_form是独一无二的，不回牵扯到之前的referencethis.setState({add_edit_form})

Answer 2

你的budget_form是不是就是add_edit_form

Answer 3

console.log(that.state.budget_form);  设置之前查看值that.setState({            add_edit_form:add_edit_form},()=>{ console.log(that.state.budget_form);  设置之后查看值  })看打印的是否一样