JS.setValueFromJson Function

Format

Description

The JS.setValueFromJson function sets the value of a JavaScript variable or property from JSON representation passed to the function as the string expression json. The JSON is converted to a value or object using JSON.parse. This is a useful way to transfer data from CSPro logic to JavaScript if the data cannot be represented by a CSPro object that can be handled by the JS.setValue function. This function can be used to create new variables or properties, or to modify existing ones.

The string expression name is evaluated and can refer to a variable in CSPro's JavaScript global execution context or an object's property if the object exists globally. For example, the following values can be specified as a name:

myFunction
globalThis.myFunction
myObject.myProperty
myObject['my' + 'Property']

Return Value

The function returns a logical value of 1 (true) if the JSON is valid and the variable or property is successfully set. If JSON parsing or JavaScript evaluation ends in an uncaught exception, the function returns 0 (false) and displays an error message.

Example

JS.setValueFromJson("france", ' { "name": "France", '
' "capital": "Paris", '
' "currency": "Euro", '
' "republicNumber": 5, '
' "languages": ["French"] }');

JS.setValueFromJson("france.area", "643801");

JS.setValueFromJson("csproVersion", "8.1");

// displays: Using CSPro 8.1, I learned that France has an area of 643801 km²!
errmsg("%s", JS.eval("`Using CSPro ${csproVersion.toFixed(1)}, "
"I learned that ${france.name} has an area of ${france.area} km²!`"));