Hello
I would like to write content of structure to JSON string, and then read it back.
I tried plugin “JSON Blueprint utilities”
While “Convert struct to JSON String” prepares nice JSON string, how to read it back into structure?
That what I could do is to “Load JSON from String”, then “Get Field Names”, then iterate that names using “For Each”, then compare each string with expected name, and thru ugly ladder of selects, assign each field by hand with corresponding output structure field.
It is tedious, error-prone process, especially for larger and more complicated structures.
In my solution I would like to have some nested structures, arrays etc.
While “Convert struct to JSON String” produces nice string, then loading it back looks terrible that way.
Maybe I am doing something wrong, and there is better way?
At high level I would like to create human readable config file for my game.
While my config contains arrays of structures with fields like int, float, string, guid.
I am searching for solution to serialize such structure to human readable-editable format, and read it back.
My further experiments shows that I am doing something wrong, or library lack of support for arrays or any kind of nesting.
I have 3 element array, each element is structure that contains fields int1, int2, float1, float2.
All initialized with unique values for better understanding.
I tried to create code that would first write it to JSON file (success), and then read (that fails).
Log from that run is:
LogBlueprintUserMessages: [BP_testJSON_C_UAID_18C04DED29E2085C02_2088169055] {
"arrayFlat": [
{
"int1": 1,
"int2": 2,
"float1": 3,
"float2": 4
},
{
"int1": 11,
"int2": 12,
"float1": 13,
"float2": 14
},
{
"int1": 21,
"int2": 22,
"float1": 23,
"float2": 24
}
]
}
LogJson: Warning: Ignoring excess properties when deserializing CallFunc_GetField_OutValue
LogBlueprintUserMessages: [BP_testJSON_C_UAID_18C04DED29E2085C02_2088169055] top level name=arrayFlat success=true
LogBlueprintUserMessages: [BP_testJSON_C_UAID_18C04DED29E2085C02_2088169055] nested name=int1 floatVal=1.0 success=true
LogBlueprintUserMessages: [BP_testJSON_C_UAID_18C04DED29E2085C02_2088169055] nested name=int2 floatVal=2.0 success=true
LogBlueprintUserMessages: [BP_testJSON_C_UAID_18C04DED29E2085C02_2088169055] nested name=float1 floatVal=3.0 success=true
LogBlueprintUserMessages: [BP_testJSON_C_UAID_18C04DED29E2085C02_2088169055] nested name=float2 floatVal=4.0 success=true
So at first level only arrayFlat is found - ok, that was expected.
But at second level there is no data about array, but looks like first element was parsed, and both loops ends.
Is this possible to do proper nested read of this JSON file that way?
It would be still far away from my “dream” function that would simply deserialize JSONstring->structure in opposite way to “Convert struct to JSON String”, but event that what I already tried seems not work at all.
Array Flat contains 3 Indexed arrays of data (0, 1, 2)
"arrayFlat": [
{ // Index 0
"int1": 1,
"int2": 2,
"float1": 3,
"float2": 4
},
{ // Index 1
"int1": 11,
"int2": 12,
"float1": 13,
"float2": 14
},
{ // Index 2
"int1": 21,
"int2": 22,
"float1": 23,
"float2": 24
}
]
- Convert Struct to JSON string
- Break complex string into substrings which outputs an array of JSON strings
- Loop the Array (foreach) → Loop the strings (for)
