从json格式化字符串中检索键的位置。

Question

我希望从输入字符串中获得json键的位置(起始偏移量)。

例如，我想检索键-1的位置：

{
    "entity" : {
        "key-1" : "a",
        "key-2" : "b"
    }
}`;

我尝试过许多不同的方法，但有一个最接近的方法：

function getOffset(path:string)
{
    let testData = `
    { 
        "entity" : {
            "key-1" : "a",
            "key-2" : "b"
        }
    }`;

    let jsonMap = require('json-source-map');
    let stringify = jsonMap.stringify(JSON.parse((testData)));
    console.log(stringify);
    let pointer = stringify.pointers[path];
    return pointer.key;
}

export function CheckSyntax(editor:vscode.TextEditor) 
{
    let key = getOffset("/entity/key-1");
    console.log(key);
}

问题是字符串被转换为对象，并松散了有关原始字符串( testData )的所有引用。所以我有一个偏移量，但是它相对于一个新的jsonString。

注意:使用find并不能达到目的，因为会有许多具有相同子键名的对象。

注之二:最后一个目标是在进行一些内部检查后突出显示一个错误的键。

Answer 1

参见.stringify文档中的示例。如果你去掉无用的绞线：

var jsonMap = require('json-source-map');
CheckSyntax(`{
    "entity" : {
        "key-1" : "a",
        "key-2" : "b"
    }
}`);
function getOffset(path)
{
    let testData = `
    { 
        "entity" : {
            "key-1" : "a",
            "key-2" : "b"
        }
    }`;

    let jsonMap = require('json-source-map');
    let stringify = jsonMap.parse(testData);
    console.log(JSON.stringify(stringify, null, 2));
    let pointer = stringify.pointers[path];
    return pointer.key;
}

function CheckSyntax(editor) 
{
    let key = getOffset("/entity/key-1");
    console.log(key);
}

并获得您想要的结果(键和字符串输出切换)：

null: Object {line: 3, column: 12, pos: 41}
{
  "data": {
    "entity": {
      "key-1": "a",
      "key-2": "b"
    }
  },
  "pointers": {
    "": {
      "value": {
        "line": 1,
        "column": 4,
        "pos": 5
      },
      "valueEnd": {
        "line": 6,
        "column": 5,
        "pos": 97
      }
    },
    "/entity": {
      "key": {
        "line": 2,
        "column": 8,
        "pos": 16
      },
      "keyEnd": {
        "line": 2,
        "column": 16,
        "pos": 24
      },
      "value": {
        "line": 2,
        "column": 19,
        "pos": 27
      },
      "valueEnd": {
        "line": 5,
        "column": 9,
        "pos": 91
      }
    },
    "/entity/key-1": {
      "key": {
        "line": 3,
        "column": 12,
        "pos": 41
      },
      "keyEnd": {
        "line": 3,
        "column": 19,
        "pos": 48
      },
      "value": {
        "line": 3,
        "column": 22,
        "pos": 51
      },
      "valueEnd": {
        "line": 3,
        "column": 25,
        "pos": 54
      }
    },
    "/entity/key-2": {
      "key": {
        "line": 4,
        "column": 12,
        "pos": 68
      },
      "keyEnd": {
        "line": 4,
        "column": 19,
        "pos": 75
      },
      "value": {
        "line": 4,
        "column": 22,
        "pos": 78
      },
      "valueEnd": {
        "line": 4,
        "column": 25,
        "pos": 81
      }
    }
  }
}