parsing-json.ts

interface Product {
    id: number;
    name: string;
    price: number;
    // Mark optional with '?'
    description?: string; 
  }
  
  const rawJson = '{ "id": 123, "name": "Widget", "price": 9.99 }';
  
  function parseProduct(jsonString: string): Product | null {
    try {
      const productData = JSON.parse(jsonString);
  
      // Ensure the parsed data has the correct structure 
      if (
          typeof productData.id === "number" && 
          typeof productData.name === "string" &&  
          typeof productData.price === "number" 
      ) {
        return productData as Product; // Assertion if checks pass
      } else {
        return null; // Invalid product data
      }
  
    } catch (error) {
      console.error("Error parsing JSON:", error);
      return null; 
    }
  }
  
  const product = parseProduct(rawJson);
  if (product) {
    console.log("Product:", product);
  } else {
    console.log("Failed to parse product data");
  }