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How to check whether an array contains a string in TypeScript?

To check whether an array contains a string in TypeScript, we call the includes method.

For instance, we write

console.log(channelArray.includes("three"));

to check if the channelArray has 'three' in it with includes.

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How to fix the “TS7053 Element implicitly has an ‘any’ type” error in TypeScript?

To fix the "TS7053 Element implicitly has an ‘any’ type" error in TypeScript, we can create a type with an index signature that allows any properties to be in the object.

For instance, we write

const myObj: { [index: string]: any } = {};

to set myObj to the { [index: string]: any } type so that the object assigned can have any properties in it.

The { [index: string]: any } type is an object type that allows any string keys as its property name and any value as their values.

The error will then go away since we set myObj to an object literal.

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How to loop through an array in TypeScript?

To loop through an array in TypeScript, we can use a for-of loop.

For instance, we write

for (const product of products) {
  console.log(product.productDesc);
}

to loop through the products array with a for-of loop.

In it, we log the productDesc property of the products object entry being looped through, which is stored in product.

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How to import image with TypeScript?

To import image with TypeScript, we can use declare to declare the type for image files.

For instance, we write

declare module "*.png" {
  const value: any;
  export = value;
}

to declare the type for modules with the .png extension.

We just allow any property to be exported with

const value: any;
export = value;

And then we can import .png files without errors since png files are recognized by the TypeScript compiler after we added the module declaration.

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How to fix the ‘ts2769: no overload matches this call.’ error with TypeScript?

To fix the ‘ts2769: no overload matches this call.’ error with TypeScript, we should call a function with the arguments that matches one of the signatures of the function.

For instance, we write

function foo(str: "hello"): string;
function foo(str: "world"): string;
function foo(str: "hello" | "world"): string {
  return str;
}

foo("hello");

to define the foo function with multiple signatures.

It accepts the str parameter which can be either 'hello' or 'world'.

And then we call foo with 'hello' to we avoid the error.

If we call foo with something other than 'hello' or 'world', then we get this error.