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    Validate a Single React Input

    Gosha ArinichGosha Arinich

    Learn to validate the presence of text in a single React input by displaying a green-check or a red-cross emoji next to it.

    We'll do this by creating a variable isValid that will return true if any text is found in the state property hooked up to the input field. This newly created variable will be used in a ternary to display the correct emoji mentioned above.



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    Instructor: 00:01 We have this simple React application that displays a name input. The value of that input is stored in state. It's sent past to the input component, and whenever that value changes, the handleChange function updates the state.

    00:19 We can see that the input is working. Now, to validate the input, we will create a const, isValid. The input will be valid when the value is not an empty string. We can now use the isValid variable to conditionally render.

    00:36 If isValid is true, then we'll show a green checkmark. Otherwise, we'll show a red cross. Now, we can see that the input shows a red cross next to it, but once we type something in, it's working.