javascript strange comparison of strings

 

This question already has an answer here:

  • Which equals operator (== vs ===) should be used in JavaScript comparisons? 50 answers
  • Difference between == and === in JavaScript [duplicate] 2 answers

    • If the output of console.log(response) is 

    {"type":"success","desc":"something"}

    then response is most likely still a string (containing JSON), and strings don't have a type property: 

    > "foo".type == "error" // `undefined` is never equal to a string
false

    Objects usually look differently in the console: 

    > console.log({"type":"success","desc":"something"})
Object {type: "success", desc: "something"} // in Chrome and Firefox at least

    Solution : Parse the string first: 

    response = JSON.parse(response);

    Related to jQuery:

    I noticed that you intend to let jQuery parse the JSON for you, but you are passing "json" to the wrong function. You have to pass it to $.post(...) , not to .done(...) : 

    $.post("sendEmail.php", post_data, "json").done(...);
// instead of 
// $.post("sendEmail.php", post_data).done(..., "json");

    Then you don't need to parse it manually.

    Related: Parse JSON in JavaScript?

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