需要将光标位置设置到 contentEditable div 的末尾，选择和范围对象的问题

2022-01-24 00:00:00 range javascript getselection

我暂时忘记了跨浏览器兼容性，我只是想让它工作.我正在尝试修改位于 typegreek.com 的脚本(您可能不需要知道这一点) here 可以找到基本脚本.基本上它的作用是当您输入字符时，它将您输入的字符转换为希腊字符并将其打印到屏幕上.我想要做的是让它在 contentEditable div 上工作(它只适用于 Textareas)

I'm forgetting about cross-browser compatibility for the moment, I just want this to work. What I'm doing is trying to modify a script (and you probably don't need to know this) located at typegreek.com The basic script is found here. Basically what it does is when you type in characters, it converts the character your are typing into greek characters and prints it onto the screen. What I'm trying to do is to get it to work on contentEditable div's (It only works for Textareas)

我的问题在于这个函数:用户键入一个键，它被转换为一个希腊键，然后转到一个函数，它通过一些 if 进行排序，最后是我可以添加 div 支持的地方.这是我到目前为止所拥有的，

My issue is with this one function: The user types a key, it get's converted to a greek key, and goes to a function, it gets sorted through some if's, and where it ends up is where I can add div support. Here is what I have so far,

myField 是 div，myValue 是希腊字符.

myField is the div, myValue is the greek character.

//Get selection object...
var userSelection
 if (window.getSelection) {userSelection = window.getSelection();}
 else if (document.selection) {userSelection = document.selection.createRange();}

//Now get the cursor position information...
var startPos = userSelection.anchorOffset;
var endPos = userSelection.focusOffset;
var cursorPos = endPos;

//Needed later when reinserting the cursor...
var rangeObj = userSelection.getRangeAt(0) 
var container = rangeObj.startContainer

//Now take the content from pos 0 -> cursor, add in myValue, then insert everything after myValue to the end of the line.
myField.textContent = myField.textContent.substring(0, startPos) + myValue + myField.textContent.substring(endPos, myField.textContent.length);

//Now the issue is, this updates the string, and returns the cursor to the beginning of the div. 
//so that at the next keypress, the character is inserted into the beginning of the div.
//So we need to reinsert the cursor where it was.

//Re-evaluate the cursor position, taking into account the added character.
  var cursorPos = endPos + myValue.length;

  //Set the caracter position.
  rangeObj.setStart(container,cursorPos)

现在，这只有在我输入的内容不超过原始文本的大小时才有效.假设我事先在 div 中有 30 个字符.如果我输入超过 30 个字符，它会添加字符 31，但会将光标放回 30.我可以在 pos.31 处键入字符 32，然后在 pos.32 处键入字符 33，但是如果我尝试将字符 34 输入，它添加字符，并将光标设置回 32.问题是如果 cursorPos 大于范围中定义的值，则添加新字符的函数会出错.有什么想法吗?

Now, this works only as long as I don't type more than the size of the original text. Say I had 30 characters in the div before hand. If I type more than that 30, it adds character 31, but places the cursor back at 30. I can type character 32 at pos.31, then character 33 at pos.32, but if I try to put character 34 in, it adds the character, and sets the cursor back at 32. The issue is that the function for adding the new character screws up if cursorPos is greater than what is defined in the range. Any ideas?

推荐答案

在 contenteditable div 中跨浏览器比在 textarea 中更容易.以下假设您的 contenteditable div 的 id 为greek".

It's easier to do this cross-browser in a contenteditable div than a textarea. The following assumes your contenteditable div has an id of "greek".

var greekChars = {
    "a": "u03b1"
    // Add character mappings here
};

function convertCharToGreek(charStr) {
    return greekChars[charStr] || "[Greek]";
}

function insertTextAtCursor(text) {
    var sel, range, textNode;
    if (window.getSelection) {
        sel = window.getSelection();
        if (sel.getRangeAt && sel.rangeCount) {
            range = sel.getRangeAt(0);
            range.deleteContents();
            textNode = document.createTextNode(text);
            range.insertNode(textNode);

            // Move caret to the end of the newly inserted text node
            range.setStart(textNode, textNode.length);
            range.setEnd(textNode, textNode.length);
            sel.removeAllRanges();
            sel.addRange(range);
        }
    } else if (document.selection && document.selection.createRange) {
        range = document.selection.createRange();
        range.pasteHTML(text);
    }
}

var div = document.getElementById("greek");

div.onkeypress = function(evt) {
    evt = evt || window.event;
    var charCode = (typeof evt.which == "undefined") ? evt.keyCode : evt.which;
    if (charCode) {
        var charStr = String.fromCharCode(charCode);
        var greek = convertCharToGreek(charStr);
        insertTextAtCursor(greek);
        return false;
    }
}

相关文章