如何重新开始对象中键的计数？

Question

What is the problem :

这是我存储在 this.state.jsondata 中的数据：

{
  label{0:1,1:1}
  prediction{0:0,1:1}
  text{0:"abc",1:"def"}
}

这个在前 JSON.stringify(this.state.jsondata) :

{"label":{"1":0,"2":0,"3":0,"4":0},"text":{"1":"aa","2":"bb,"3":"cc","4":"dd"},"prediction":{"1":2,"2":2,"3":2,"4":2}}

当我使用此代码删除一个元素时：

    removeData = (keyToRemove) => {
        // create a deep copy of the object
        const clonedJsonData = JSON.parse(JSON.stringify(this.state.jsondata))
        // now mutate this cloned object directly
        Object.keys(clonedJsonData).forEach(key => delete clonedJsonData[key][keyToRemove])
        // set the state
        this.state.jsondata = clonedJsonData

this.state.jsondata 变为：

{
  label{1:1}
  prediction{1:1}
  text{1:"def"}
}

而不是像 :

那样从 0 开始

{
 label{0:1}
 prediction{0:1}
 text{0:"def"}
}

所以基本上我想将 key 设置回“0, 1, 2, 3..”

What have I tried :

我试图遍历我的数据，但是我循环遍历它的方式有问题：

    removeData = (keyToRemove) => {
        // create a deep copy of the object
        const clonedJsonData = JSON.parse(JSON.stringify(this.state.jsondata))
        // now mutate this cloned object directly
        Object.keys(clonedJsonData).forEach(key => delete clonedJsonData[key][keyToRemove])
        // reset keys value
        let i = 0
        Object.keys(clonedJsonData).forEach(function(key) {
            Object.keys(clonedJsonData[key]).forEach(function(k) {
                var newkey = i++;
                clonedJsonData[key][k] = clonedJsonData[key][k];
                delete clonedJsonData[key][k];
            })
        })
        // set the state
        this.state.jsondata = clonedJsonData
        
    }

What is the expected output ?

预期输出为：

{
 label{0:1}
 prediction{0:1}
 text{0:"def"}
}

Answer 1

如果你的键基本上代表值的索引，为什么不使用数组呢？ { 标签：[1,1]，预测：[0,1]，文本：["abc","def"] }

如果您现在删除每个数组中的第一个条目，data.text[0] 将为“def”，依此类推...

编辑：

如果您不想转换数据，则必须小心，尤其是当您对整个内容进行解析和字符串化，然后遍历键时。之后它们不必按相同的顺序排列。

除了克隆对象、删除要删除的键然后更新所有键之外，您还可以手动复制对象并留下要删除的键

var data = {label: {0:0, 1:0}, prediction: {0:0, 1:1}, text: {0:'abc',1:'def'}};
console.log("Original Data");
console.log(data);

removeData = (data, keyToRemove) => {
    var ret = {};
    Object.keys(data).forEach(key=>{
        ret[key] = {};
        let idx = 0;
    
        for (let dataIdx = 0; dataIdx < Object.keys(data[key]).length; dataIdx++) {
            if (dataIdx.toString() !== keyToRemove) {
                ret[key][idx.toString()] = data[key][dataIdx.toString()];
                idx++;
          }
        }
    }); 
  
  return ret;
}

var reducedData = removeData(data,"0");
console.log("Reduced Data");
console.log(reducedData);

请注意，我没有在键上循环，所以我没有弄错顺序。请注意，我还通过将数据对象作为参数移交来消除了原始函数的副作用。

Answer 2

这就是我的做法

    removeData = (keyToRemove) => {
        // create a deep copy of the object
        const clonedJsonData = JSON.parse(JSON.stringify(this.state.jsondata))
        // now mutate this cloned object directly
        Object.keys(clonedJsonData).forEach(key => delete clonedJsonData[key][keyToRemove])
        // reset keys value 
        let i = 0
        Object.keys(clonedJsonData).forEach(function eachKey(key) {
            i = 0
            Object.keys(clonedJsonData[key]).forEach(function eachKey(kkey) {
                var newkey = i++;
                clonedJsonData[key][newkey] = clonedJsonData[key][kkey];
                
            });
            delete clonedJsonData[key][i];
        });
        
        // set the state
        this.state.jsondata = clonedJsonData
}

如何重新开始对象中键的计数？

How to restart the numeration of the keys in a object?

javascript

arrays

json

key

object