how do you extract JSON boolean value

[dahlin]

Hi, I am using the JSON API to extract values from a string.

I got the extracted string value out [0] as expected but when I try to read out the Boolean value I got an error (Not a JSON Scalar: 'null' ).

/dahlin

[Tim_S]

I believe you want to wire the Get:Boolean to the output of the Get:from JSON rather than the Get:sub-Item with the way you have the name array wired.

The error is correct in that there is no Boolean in the JSON from the Get:sub-Item. A Boolean value in the JSON would be something like:

"MaximizeOnStart": false

I expect a value of [0] indicates a NULL rather than a logical 0.

[dahlin]

Hi Tim,

I tried to change the file input to 'false' instead of '0' and rewire the other wire that you pointed out but it is still the same problem.

When probing the JSON wire it says it is a JSON Object.lvclass ?  instead of Scalar?

[Tim_S]

I would expect the sub-Item to be a scalar and the input to the Get:Boolean to be a JSON object.

What does your JSON file look like? I would expect it to be something like below.

{
  "blemishResults": {
    "passfail": {
      "Blemishes_all_passed": false
    }
  }
}

JSON test.vi

[dahlin]

OK, when I compared to your JSON file I found the problem: I had written true or false with brackets like this [true] [false].

Thank you Tim!

/dahlin

[JKSH]

4 hours ago, dahlin said:

OK, when I compared to your JSON file I found the problem: I had written true or false with brackets like this [true] [false].

In JSON, square brackets represent arrays. So, this is an array that contains one Boolean element:

[true]

 

This is an array containing three Boolean elements:

[true, false, true]