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AnswerRe: calendar validation Pin
Jeremy Falcon5-Jan-23 11:13
professionalJeremy Falcon5-Jan-23 11:13 
AnswerRe: calendar validation Pin
Jeremy Falcon5-Jan-23 11:17
professionalJeremy Falcon5-Jan-23 11:17 
Questionhow to modify cloned element draggable attribute ? Pin
VernonM23-Dec-22 10:37
VernonM23-Dec-22 10:37 
AnswerRe: how to modify cloned element draggable attribute ? Pin
VernonM23-Dec-22 14:57
VernonM23-Dec-22 14:57 
AnswerRe: how to modify cloned element draggable attribute ? Pin
VernonM24-Dec-22 2:43
VernonM24-Dec-22 2:43 
GeneralRe: how to modify cloned element draggable attribute ? Pin
VernonM25-Dec-22 3:51
VernonM25-Dec-22 3:51 
QuestionNeed Help with Drag n Drop... Pin
VernonM21-Dec-22 10:26
VernonM21-Dec-22 10:26 
AnswerRe: Need Help with Drag n Drop... Pin
Richard Deeming21-Dec-22 21:26
mveRichard Deeming21-Dec-22 21:26 
Only one of your draggable elements has an id. For any of the others, you set the dataTransfer data to an undefined value. When you drop that, you call getElementById(undefined), which returns null. You then pass null to appendChild, which throws the error.

Add a unique id to every element you want to drag, and validate the element when you drop it.
JavaScript
let uid = 0;

function drag(ev) {
    const id = e.target.id;
    if (!id) {
        id = `_auto_generated_id_${uid}`;
        e.target.id = id;
        uid++;
    }
    
    ev.dataTransfer.setData("text", id);
    console.debug("drag", e.target, id);
}

function drop(ev) {
    ev.preventDefault();
    
    const id = ev.dataTransfer.getData("text");
    if (!id) {
        console.warn("Drop with no ID", ev.dataTransfer);
        return;
    }

    const element = document.getElementById(id);
    if (!element) {
        console.warn("Element not found", id);
        return;
    }
    
    ev.target.appendChild(element);
}




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- Homer

GeneralRe: Need Help with Drag n Drop... Pin
VernonM22-Dec-22 5:50
VernonM22-Dec-22 5:50 
QuestionJavascript cookies Pin
Member 158197443-Nov-22 20:46
Member 158197443-Nov-22 20:46 
AnswerRe: Javascript cookies Pin
Jeremy Falcon17-Nov-22 13:32
professionalJeremy Falcon17-Nov-22 13:32 
AnswerRe: Javascript cookies Pin
JohnG1013-Dec-22 0:40
JohnG1013-Dec-22 0:40 
Questionwhy javascript onchange not triggered for persian characters ? Pin
shaho zakaryaee23-Oct-22 21:47
shaho zakaryaee23-Oct-22 21:47 
AnswerRe: why javascript onchange not triggered for persian characters ? Pin
Richard Deeming23-Oct-22 21:49
mveRichard Deeming23-Oct-22 21:49 
AnswerRe: why javascript onchange not triggered for persian characters ? Pin
shaho zakaryaee23-Oct-22 21:58
shaho zakaryaee23-Oct-22 21:58 
GeneralRe: why javascript onchange not triggered for persian characters ? Pin
Jeremy Falcon26-Oct-22 11:10
professionalJeremy Falcon26-Oct-22 11:10 
QuestionDodger game with eventListener Pin
Ali Ibrahim jasim16-Oct-22 2:54
Ali Ibrahim jasim16-Oct-22 2:54 
AnswerRe: Dodger game with eventListener Pin
Jeremy Falcon26-Oct-22 11:26
professionalJeremy Falcon26-Oct-22 11:26 
QuestionHTML5 Nested drag and drop using vuejs2 Pin
Maseeha K30-Sep-22 23:40
Maseeha K30-Sep-22 23:40 
AnswerRe: HTML5 Nested drag and drop using vuejs2 Pin
Jeremy Falcon26-Oct-22 11:12
professionalJeremy Falcon26-Oct-22 11:12 
Questiontrying to get to grips with parsing from a JSON file Pin
DSB Audio (David Sweeney-Bear)30-Sep-22 4:22
DSB Audio (David Sweeney-Bear)30-Sep-22 4:22 
AnswerRe: trying to get to grips with parsing from a JSON file Pin
Richard MacCutchan30-Sep-22 4:53
mveRichard MacCutchan30-Sep-22 4:53 
GeneralRe: trying to get to grips with parsing from a JSON file Pin
DSB Audio (David Sweeney-Bear)30-Sep-22 5:42
DSB Audio (David Sweeney-Bear)30-Sep-22 5:42 
GeneralRe: trying to get to grips with parsing from a JSON file Pin
Richard MacCutchan30-Sep-22 5:49
mveRichard MacCutchan30-Sep-22 5:49 
GeneralRe: trying to get to grips with parsing from a JSON file Pin
DSB Audio (David Sweeney-Bear)30-Sep-22 7:57
DSB Audio (David Sweeney-Bear)30-Sep-22 7:57 

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