JavaScript Error: 'item.parentId.includes is not a function' - Troubleshooting and Solution

The error message 'item.parentId.includes is not a function' indicates that the 'includes' method is not available for the 'parentId' property of the 'item' object. This usually occurs when 'item.parentId' is not a string, and the 'includes' method is only applicable to strings.

To fix this issue, you should check if 'item.parentId' is a string before using the 'includes' method. Here's the updated code:

handleQuery(item) {
  console.log(item, 'item');
  if (this.searchvalue) {
    return this.voucherGroupList.filter((item) => {
      if (item.voucherGroupCode && typeof item.parentId === 'string') {
        // Check if item.parentId is a string before using includes method
        return (
          item.voucherGroupCode.includes(this.searchvalue) ||
          item.parentId.includes(this.searchvalue)
        );
      }
    });
  } else {
    return this.voucherGroupList;
  }
}

By adding the typeof item.parentId === 'string' condition, the code ensures that the 'includes' method is only used when the 'parentId' property is a string, effectively preventing the error.