How to Decode a JSON String Containing Nested JSON-Encoded Strings?

Decode JSON with Included JSON-Encoded Strings

Problem

When attempting to decode a JSON string containing a nested JSON object, the application receives an error: "invalid character 'h' after object key:value pair."

Solution

The error is caused by an invalid character in the nested JSON object's value. To properly decode the JSON, it must be done in two steps:

type main struct {
  Name string   `json:"name"`
  Args []string `json:"args"`
}

type arg struct {
  Method string `json:"method"`
  Params par    `json:"params"`
}
type par struct {
  Channel   string `json:"channel,omitempty"`
  Name      string `json:"name,omitempty"`
  NameColor string `json:"nameColor,omitempty"`
  Text      string `json:"text,omitempty"`
  Time      int64  `json:"time,omitempty"`
}

// Parse input JSON string
str := `{"name":"message","args":["{\"method\":\"chatMsg\",\"params\":{\"channel\":\"channel\",\"name\":\"name\",\"nameColor\":\"B5B11E\",\"text\":\"<a href=\\"https://play.spotify.com/browse\\" target=\\"_blank\\">https://play.spotify.com/browse</a>\",\"time\":1455397119}}"]}`
var m main
if err := json.Unmarshal([]byte(str), &m); err != nil {
    log.Fatal(err)
}

// Decode nested JSON object
var args arg
if err := json.Unmarshal([]byte(m.Args[0]), &args); err != nil {
    log.Fatal(err)
}

The first step decodes the outer JSON object into a main struct, which contains an array of strings. The second step loops through the array and decodes each string as a nested JSON object. This allows the application to properly parse the JSON data and avoid the error.

The above is the detailed content of How to Decode a JSON String Containing Nested JSON-Encoded Strings?. For more information, please follow other related articles on the PHP Chinese website!