[ React ] null값 허용하기

//.tsconfig.json에서 
{
 "compilerOptions": {
 	"target": "es5",
    "lib": [ 
    	"dom",
        "dom.iterable",
        "esnext"
 		],
 	"allowJs": true,
    "skipLibCheck": true,
    "esModuleInterop": true,
    "allowSyntheticDefaultImports": true,
    "strict": true,
    "forceConsistentCasingInFileNames": true,
    "module": "esnext",
    "moduleResolution": "node",
    "resolveJsonModule": true,
    "noEmit": true,
    "jsx": "react-jsx",
    "isolatedModules": true,
    "noFallthroughCasesInSwitch": true,
    "strictNullChecks": false // 이부분을 추가하면 null 허용
    },
 "include": [ "src" ]
 }