我目前有一个textarea,我需要控制粘贴的文本,

基本上我需要能够将用户想要粘贴的任何内容粘贴到textarea并将其放入变量中.

然后,我将确定它们粘贴文本的位置和字符串的大小,以便从textarea中删除它,

然后在最后以我自己的方式处理变量中的文本.

我的问题：如何在用户粘贴的变量中获取文本的副本？

谢谢.

解决方法:

我几天前回答了一个类似的问题：Detect pasted text with ctrl+v or right click -> paste.这次我已经包含了很长的函数,可以准确地在IE中的textarea中获取选择边界;其余的相对简单.

您可以使用粘贴事件来检测大多数浏览器中的粘贴(特别是Firefox 2).处理粘贴事件时,记录当前选择,然后设置一个在粘贴完成后调用函数的简短计时器.然后,此函数可以比较长度以了解在何处查找粘贴的内容.类似于以下内容：

function getSelectionBoundary(el, start) {

var property = start ? "selectionStart" : "selectionEnd";

var originalValue, textInputRange, precedingRange, pos, bookmark, isAtEnd;

if (typeof el[property] == "number") {

return el[property];

} else if (document.selection && document.selection.createRange) {

el.focus();

var range = document.selection.createRange();

if (range) {

// Collapse the selected range if the selection is not a caret

if (document.selection.type == "Text") {

range.collapse(!!start);

}

originalValue = el.value;

textInputRange = el.createTextRange();

precedingRange = el.createTextRange();

pos = 0;

bookmark = range.getBookmark();

textInputRange.moveToBookmark(bookmark);

if (/[\r\n]/.test(originalValue)) {

// Trickier case where input value contains line breaks

// Test whether the selection range is at the end of the

// text input by moving it on by one character and

// checking if it's still within the text input.

try {

range.move("character", 1);

isAtEnd = (range.parentElement() != el);

} catch (ex) {

log.warn("Error moving range", ex);

isAtEnd = true;

}

range.moveToBookmark(bookmark);

if (isAtEnd) {

pos = originalValue.length;

} else {

// Insert a character in the text input range and use

// that as a marker

textInputRange.text = " ";

precedingRange.setEndPoint("EndToStart", textInputRange);

pos = precedingRange.text.length - 1;

// Delete the inserted character

textInputRange.moveStart("character", -1);

textInputRange.text = "";

}

} else {

// Easier case where input value contains no line breaks

precedingRange.setEndPoint("EndToStart", textInputRange);

pos = precedingRange.text.length;

}

return pos;

}

}

return 0;

}

function getTextAreaSelection(textarea) {

var start = getSelectionBoundary(textarea, true),

end = getSelectionBoundary(textarea, false);

return {

start: start,

end: end,

length: end - start,

text: textarea.value.slice(start, end)

};

}

function detectPaste(textarea, callback) {

textarea.onpaste = function() {

var sel = getTextAreaSelection(textarea);

var initialLength = textarea.value.length;

window.setTimeout(function() {

var val = textarea.value;

var pastedTextLength = val.length - (initialLength - sel.length);

var end = sel.start + pastedTextLength;

callback({

start: sel.start,

end: end,

length: pastedTextLength,

text: val.slice(sel.start, end),

replacedText: sel.text

});

}, 1);

};

}

window.onload = function() {

var textarea = document.getElementById("your_textarea");

detectPaste(textarea, function(pasteInfo) {

var val = textarea.value;

// Delete the pasted text and restore any previously selected text

textarea.value = val.slice(0, pasteInfo.start) +

pasteInfo.replacedText + val.slice(pasteInfo.end);

alert(pasteInfo.text);

});

};

标签：javascript,events,textarea,paste

来源： https://codeday.me/bug/20190701/1342243.html