Please someone should help me ...ypeError: Cannot read properties of undefined (reading 'length')

Moralis General
#1 
  useEffect(() => {
        // declare the async data fetching function
        const fetchData = async () => {
          // get the data from the api
          const params = {ethAddress: Address};
          const data = await Moralis.Cloud.run('getFollowers', params);
         const userdata= await Moralis.Cloud.run('getUser', params);
          // convert the data to json
          //const json = await data.json();
      
          // set state with the result
          setfollowers(data);
          setiscurrentuser(userdata.username);{
      
            for (let i = 0; i < data.followers.length; i++) {
             // dict[res.data.followers[i].id]=1;
               setfollowers_id(prevState => ({
                 ...prevState,
                 [data.followers[i].id]:1, 
              }));  
              
            }
          }
          
        }
      
        // call the function
        fetchData()
          // make sure to catch any error
          .catch(console.error);;
      }, [])
#2

You can try to check the value of that variable.

#3

Please help me …I am new to this …thank you

#4

You can try to add some debugging with console.log

#5

Please can you show me an example

#6

An example: console.log(variable_name)

#7

try to do as @cryptokid says and console.log(data.followers) it must be undefined

I’m not very sure how you structure your state, but if you don’t initialize anything in useState, then I also suggest you to initialize it with an empty array

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