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Javascript – this.value always comes back undefined – React

I am working on adding a value to localstorage with an Onclick event. It is supposed to take the innerHTML from the button and put the value into the local storage as the "Cemetery" value.

I have tried multiple different ways of getting the value but I keep getting undefined. If you could give me a hand and some pointers, that would be great!

const CemeteryPage = () => {
 
  
function setCemetery(ListItem) {
  
    localStorage.setItem("Cemetery", ListItem.value)

 

}
  return (
    <>
    <div className='Header'>
        <h1>What <span>cemetery</span> is this stone going to?</h1>
       <div className='Line'></div>
    </div>
     <div class="CemeteryList">
        <div className="ListItem" onClick={function(){setCemetery(this)}}>
        St Anthony's Cemetery
        </div>
        <div className="ListItem" onClick={function(){setCemetery(this)}}>
       Hillside Cemetery
        </div>
      </div>
        
    </>
  )
}

I tried using .getAttribute, .attributes[], I tried adding a value attribute and pulling it from there but still got undefined.

Tags:

2

Answers


  1. 0

    In the provided code snippet, the ListItem being passed to the setCemetery function is expected to have a value property. However, in React, event handlers like onClick by default do not pass the DOM element directly but rather the event object itself. Therefore, this inside the onClick function does not refer to the DOM element itself.

    To fix this issue, you can modify the setCemetery function to directly accept the value of the cemetery instead of expecting an object with a value property. Here’s the modified code:

    const CemeteryPage = () => {
  function setCemetery(value) {
    localStorage.setItem("Cemetery", value);
  }

  return (
     <>
      <div className='Header'>
       <h1>What <span>cemetery</span> is this stone going to?</h1>
       <div className='Line'></div>
     </div>
     <div class="CemeteryList">
      <div className="ListItem" onClick={() => setCemetery("St Anthony's Cemetery")}>
        St Anthony's Cemetery
      </div>
      <div className="ListItem" onClick={() => setCemetery("Hillside Cemetery")}>
      Hillside Cemetery
      </div>
    </div>
   </>
);
}
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  2. 0

    You tried to (this) as an argument to the setCemetery function, which wont work cos that is the entire DOM. The below should work.

    const CemeteryPage = () => {
  const handleSetCemetry = (cemetery) => {
    localStorage.setItem("cemetery", cemetery);
  };

  return (
    <>
      <div className="Header">
        <h1>
          What <span>cemetery</span> is this stone going to?
        </h1>
        <div className="Line"></div>
      </div>
      <div className="CemeteryList">
        <div
          className="ListItem"
          onClick={(e) => handleSetCemetry(e.target.innerText)}
        >
          St Anthony's Cemetery
        </div>
        <div
          className="ListItem"
          onClick={(e) => handleSetCemetry(e.target.innerText)}
        >
          Hillside Cemetery
        </div>
      </div>
    </>
  );
};
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