Initializing JSON object in TypeScript

Question

I'm new to TypeScript and I'm stuck at working with JSON. I need to create a simple JSON object and I keep on failing doing so. Here are my first attempts:

output: JSON; //declaration
this.output = {
"col1":{"Attribute1": "value1", "Attribute2": "value2", "Attribute3": "value3"},
"col2":{"Attribute1": "value4", "Attribute2": "value5", "Attribute3": "value6"}, 
"col3":{"Attribute1": "value7", "Attribute2": "value8", "Attribute3": "value9"} 
}

This doesn't work. I guess I should work with JSON.stringify function. Here's my attempt:

obj: any; //new object declaration
this.obj = {
"col1":{"Attribute1": "value1", "Attribute2": "value2", "Attribute3": "value3"},
"col2":{"Attribute1": "value4", "Attribute2": "value5", "Attribute3": "value6"}, 
"col3":{"Attribute1": "value7", "Attribute2": "value8", "Attribute3": "value9"} 
}
this.output.stringify(this.obj);

But this still invokes TypeError. So to summarize my question: how to properly create and initialize JSON object in TypeScript?

Answer 1

I've eventually figured it out. All I had to do was to create data to "any" variable like this:

output: JSON;
obj: any = 
{
"col1":{"Attribute1": "value1", "Attribute2": "value2", "Attribute3": "value3"},
"col2":{"Attribute1": "value4", "Attribute2": "value5", "Attribute3": "value6"}, 
"col3":{"Attribute1": "value7", "Attribute2": "value8", "Attribute3": "value9"} 
};

and then cast it to JSON object:

this.output = <JSON>this.obj;

Answer 2

You can also do the following

const rememberUser:JSON = <JSON><unknown>{
        "username": this.credentialsForm.value.username,
        "password": this.credentialsForm.value.password
      }

Answer 3

It worked for me in Angular 2.4.0 Stable by doing this:

var request: any = {};
request.allocation = allocationFigure;