How to marshal JSON with bigints?

问题

I have a json that contains a field with a bigint

{"NETWORK_ID": 6000370005980500000071}

The format I have before marshaling is map[string]interface{}

When I marshal it and print to console everything seems to be fine but this field actually creates problems due to its size in other mediums so I want to serialize it as a string.

UseNumber() seems to be for this purpose but it's only for decoding I think.

Is there any way that I can detect this kind of bigint number and make them serialize as strings?

回答1:

You'll need to create a custom type that implements the json.Marshaler interface, and marshals to a string. Example:

type MyBigInt big.Int

func (i MyBigInt) MarshalJSON() ([]byte, error) {
    i2 := big.Int(i)
    return []byte(fmt.Sprintf(`"%s"`, i2.String()), nil
}

This will always marshal your custom type as a quoted decimal number.

来源：https://stackoverflow.com/questions/48802728/how-to-marshal-json-with-bigints