JavaScript获取剪贴板数据粘贴事件(跨浏览器)

web应用程序如何检测粘贴事件并检索要粘贴的数据?

我想在文本粘贴到富文本编辑器之前删除HTML内容。

在粘贴后清理文本是有效的，但问题是所有以前的格式都会丢失。例如，我可以在编辑器中编写一个句子并将其加粗，但当我粘贴新文本时，所有格式都会丢失。我只想清除粘贴的文本，并保留以前的任何格式不变。

理想情况下，解决方案应该可以跨所有现代浏览器(例如，MSIE、Gecko、Chrome和Safari)工作。

注意，MSIE有clipboardData.getData()，但我找不到其他浏览器的类似功能。

当前回答

你可以这样做:

使用这个jQuery插件的前后粘贴事件:

$.fn.pasteEvents = function( delay ) {
    if (delay == undefined) delay = 20;
    return $(this).each(function() {
        var $el = $(this);
        $el.on("paste", function() {
            $el.trigger("prepaste");
            setTimeout(function() { $el.trigger("postpaste"); }, delay);
        });
    });
};

现在你可以使用这个插件;:

$('#txt').on("prepaste", function() { 

    $(this).find("*").each(function(){

        var tmp=new Date.getTime();
        $(this).data("uid",tmp);
    });


}).pasteEvents();

$('#txt').on("postpaste", function() { 


  $(this).find("*").each(function(){

     if(!$(this).data("uid")){
        $(this).removeClass();
          $(this).removeAttr("style id");
      }
    });
}).pasteEvents();

解释

首先将所有现有元素的uid设置为data属性。

然后比较所有节点的POST PASTE事件。因此，通过比较，您可以识别新插入的元素，因为它们将有uid，然后只需从新创建的元素中删除style/class/id属性，以便您可以保留旧的格式。

2013-11-17 19:36:31

其他回答

这应该适用于所有支持onpaste事件和突变观察者的浏览器。

这个解决方案不仅仅只是获取文本，它实际上允许您在粘贴到元素之前编辑粘贴的内容。

它通过使用contentteditable, onpaste事件(所有主要浏览器支持)在突变观察者(Chrome, Firefox和IE11+支持)中工作。

步骤1

创建一个带有contentteditable的html元素

<div contenteditable="true" id="target_paste_element"></div>

步骤2

在Javascript代码中添加以下事件

document.getElementById("target_paste_element").addEventListener("paste", pasteEventVerifierEditor.bind(window, pasteCallBack), false);

我们需要绑定pasteCallBack，因为突变观察者将被异步调用。

步骤3

向代码中添加以下函数

function pasteEventVerifierEditor(callback, e)
{
   //is fired on a paste event. 
    //pastes content into another contenteditable div, mutation observer observes this, content get pasted, dom tree is copied and can be referenced through call back.
    //create temp div
    //save the caret position.
    savedCaret = saveSelection(document.getElementById("target_paste_element"));

    var tempDiv = document.createElement("div");
    tempDiv.id = "id_tempDiv_paste_editor";
    //tempDiv.style.display = "none";
    document.body.appendChild(tempDiv);
    tempDiv.contentEditable = "true";

    tempDiv.focus();

    //we have to wait for the change to occur.
    //attach a mutation observer
    if (window['MutationObserver'])
    {
        //this is new functionality
        //observer is present in firefox/chrome and IE11
        // select the target node
        // create an observer instance
        tempDiv.observer = new MutationObserver(pasteMutationObserver.bind(window, callback));
        // configuration of the observer:
        var config = { attributes: false, childList: true, characterData: true, subtree: true };

        // pass in the target node, as well as the observer options
        tempDiv.observer.observe(tempDiv, config);

    }   

}



function pasteMutationObserver(callback)
{

    document.getElementById("id_tempDiv_paste_editor").observer.disconnect();
    delete document.getElementById("id_tempDiv_paste_editor").observer;

    if (callback)
    {
        //return the copied dom tree to the supplied callback.
        //copy to avoid closures.
        callback.apply(document.getElementById("id_tempDiv_paste_editor").cloneNode(true));
    }
    document.body.removeChild(document.getElementById("id_tempDiv_paste_editor"));

}

function pasteCallBack()
{
    //paste the content into the element.
    restoreSelection(document.getElementById("target_paste_element"), savedCaret);
    delete savedCaret;

    pasteHtmlAtCaret(this.innerHTML, false, true);
}   


saveSelection = function(containerEl) {
if (containerEl == document.activeElement)
{
    var range = window.getSelection().getRangeAt(0);
    var preSelectionRange = range.cloneRange();
    preSelectionRange.selectNodeContents(containerEl);
    preSelectionRange.setEnd(range.startContainer, range.startOffset);
    var start = preSelectionRange.toString().length;

    return {
        start: start,
        end: start + range.toString().length
    };
}
};

restoreSelection = function(containerEl, savedSel) {
    containerEl.focus();
    var charIndex = 0, range = document.createRange();
    range.setStart(containerEl, 0);
    range.collapse(true);
    var nodeStack = [containerEl], node, foundStart = false, stop = false;

    while (!stop && (node = nodeStack.pop())) {
        if (node.nodeType == 3) {
            var nextCharIndex = charIndex + node.length;
            if (!foundStart && savedSel.start >= charIndex && savedSel.start <= nextCharIndex) {
                range.setStart(node, savedSel.start - charIndex);
                foundStart = true;
            }
            if (foundStart && savedSel.end >= charIndex && savedSel.end <= nextCharIndex) {
                range.setEnd(node, savedSel.end - charIndex);
                stop = true;
            }
            charIndex = nextCharIndex;
        } else {
            var i = node.childNodes.length;
            while (i--) {
                nodeStack.push(node.childNodes[i]);
            }
        }
    }

    var sel = window.getSelection();
    sel.removeAllRanges();
    sel.addRange(range);
}

function pasteHtmlAtCaret(html, returnInNode, selectPastedContent) {
//function written by Tim Down

var sel, range;
if (window.getSelection) {
    // IE9 and non-IE
    sel = window.getSelection();
    if (sel.getRangeAt && sel.rangeCount) {
        range = sel.getRangeAt(0);
        range.deleteContents();

        // Range.createContextualFragment() would be useful here but is
        // only relatively recently standardized and is not supported in
        // some browsers (IE9, for one)
        var el = document.createElement("div");
        el.innerHTML = html;
        var frag = document.createDocumentFragment(), node, lastNode;
        while ( (node = el.firstChild) ) {
            lastNode = frag.appendChild(node);
        }
        var firstNode = frag.firstChild;
        range.insertNode(frag);

        // Preserve the selection
        if (lastNode) {
            range = range.cloneRange();
            if (returnInNode)
            {
                range.setStart(lastNode, 0); //this part is edited, set caret inside pasted node.
            }
            else
            {
                range.setStartAfter(lastNode); 
            }
            if (selectPastedContent) {
                range.setStartBefore(firstNode);
            } else {
                range.collapse(true);
            }
            sel.removeAllRanges();
            sel.addRange(range);
        }
    }
} else if ( (sel = document.selection) && sel.type != "Control") {
    // IE < 9
    var originalRange = sel.createRange();
    originalRange.collapse(true);
    sel.createRange().pasteHTML(html);
    if (selectPastedContent) {
        range = sel.createRange();
        range.setEndPoint("StartToStart", originalRange);
        range.select();
    }
}
}

代码的作用:

Somebody fires the paste event by using ctrl-v, contextmenu or other means In the paste event a new element with contenteditable is created (an element with contenteditable has elevated privileges) The caret position of the target element is saved. The focus is set to the new element The content gets pasted into the new element and is rendered in the DOM. The mutation observer catches this (it registers all changes to the dom tree and content). Then fires the mutation event. The dom of the pasted content gets cloned into a variable and returned to the callback. The temporary element is destroyed. The callback receives the cloned DOM. The caret is restored. You can edit this before you append it to your target. element. In this example I'm using Tim Downs functions for saving/restoring the caret and pasting HTML into the element.

例子

非常感谢Tim Down 请看这篇文章的答案:

在粘贴事件上获取文档上的粘贴内容

2014-12-16 14:52:46

这招对我很管用:

function onPasteMe(currentData, maxLen) {
    // validate max length of pasted text
    var totalCharacterCount = window.clipboardData.getData('Text').length;
}

<input type="text" onPaste="return onPasteMe(this, 50);" />

2011-10-14 17:04:17

现场演示

在Chrome / FF / IE11上测试

有一个Chrome/IE的烦恼是这些浏览器为每一行添加<div>元素。这里有一篇关于这个的文章，它可以通过设置contentteditable元素为display:inline-block来修复

选择一些突出显示的HTML并粘贴在这里:

2015-02-15 17:16:18

首先想到的是谷歌的闭包库的pastehandler http://closure-library.googlecode.com/svn/trunk/closure/goog/demos/pastehandler.html

2010-02-01 13:24:19

当用户通过浏览器的用户界面发起“粘贴”操作时，粘贴事件将被触发。

HTML

<div class="source" contenteditable="true">Try copying text from this box...</div>
<div class="target" contenteditable="true">...and pasting it into this one</div>

JavaScript

const target = document.querySelector('div.target');

target.addEventListener('paste', (event) => {
    let paste = (event.clipboardData || window.clipboardData).getData('text');
    paste = paste.toUpperCase();

    const selection = window.getSelection();
    if (!selection.rangeCount) return false;
    selection.deleteFromDocument();
    selection.getRangeAt(0).insertNode(document.createTextNode(paste));

    event.preventDefault();
});

知道更多

2021-07-06 13:46:48

JavaScript获取剪贴板数据粘贴事件(跨浏览器)

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