How to Resolve 'Cannot Unmarshal String into Go Value of Type Int64' JSON Parsing Error?

JSON Parsing Error: "Cannot Unmarshal String into Go Value of Type Int64"

Issue:
When attempting to unmarshal JSON data with a string value assigned to an int64 field, the unmarshaling process fails due to a type mismatch between the source string and the expected integer value.

Problem Details:
A custom Go struct defines an int64 field using JSON struct tags to map it to a JSON property. However, a jQuery script modifies the JSON object and encodes it as a string rather than an integer. This leads to a string being sent in place of the expected int64 value.

Solution:
To handle this type conversion issue, add the ",string" tag to the relevant field. The updated struct tag is as follows:

type tySurvey struct {
   Id   int64  `json:"id,string,omitempty"`
   Name string `json:"name,omitempty"`
}

By specifying ",string" in the JSON struct tag, the unmarshaling process will recognize that the field value can be a string and will attempt to convert it to an integer before assigning it to the int64 field.

Additional Note:
It's important to note that if the string value is the empty string, it cannot be decoded because the omitempty option is only used during encoding.

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