在大多数浏览器中，都需要Range和Selection对象。将每个选择边界指定为一个节点，并在该节点中指定偏移量。例如，要将插入符号设置为第二行文本的第五个字符，您可以执行以下操作:

function setCaret() var el =文档。getElementById(“编辑”) 咖啡壶。 var = window.getSelection() 太阳城setStart (el。childNodes [2], 5) 太阳城崩溃(真正的)。 细胞removeAllRanges()。 细胞addRange(射程)。 的 <div id=“编辑”contenteble =“真”> 文本文本<br>文本文本<br>文本文本<br> < / div > <巴顿id=“巴顿”onclick=“setCaret”()巴顿”focus > < - >

IE < 9的工作方式完全不同。如果需要支持这些浏览器，则需要不同的代码。

jsFiddle示例:http://jsfiddle.net/timdown/vXnCM/

我重构了@Liam的答案。我把它放在一个带有静态方法的类中，我让它的函数接收一个元素而不是#id，还有其他一些小调整。

这段代码特别适用于在富文本框中固定光标，例如<div contenteditable="true">。在得到下面的代码之前，我被这个问题困了好几天。

编辑:他的答案和这个答案有一个bug，涉及到按回车键。由于enter不能算作一个字符，所以按下enter键后光标的位置就乱了。如果我能够修复代码，我将更新我的答案。

edit2:为自己省去很多麻烦，确保<div contenteditable=true>为display: inline-block。这修复了一些有关Chrome浏览器把<div>而不是<br>当你按下enter的错误。

如何使用

let richText = document.getElementById('rich-text');
let offset = Cursor.getCurrentCursorPosition(richText);
// insert code here that does stuff to the innerHTML, such as adding/removing <span> tags
Cursor.setCurrentCursorPosition(offset, richText);
richText.focus();

Code

// Credit to Liam (Stack Overflow)
// https://stackoverflow.com/a/41034697/3480193
class Cursor {
    static getCurrentCursorPosition(parentElement) {
        var selection = window.getSelection(),
            charCount = -1,
            node;
        
        if (selection.focusNode) {
            if (Cursor._isChildOf(selection.focusNode, parentElement)) {
                node = selection.focusNode; 
                charCount = selection.focusOffset;
                
                while (node) {
                    if (node === parentElement) {
                        break;
                    }

                    if (node.previousSibling) {
                        node = node.previousSibling;
                        charCount += node.textContent.length;
                    } else {
                        node = node.parentNode;
                        if (node === null) {
                            break;
                        }
                    }
                }
            }
        }
        
        return charCount;
    }
    
    static setCurrentCursorPosition(chars, element) {
        if (chars >= 0) {
            var selection = window.getSelection();
            
            let range = Cursor._createRange(element, { count: chars });

            if (range) {
                range.collapse(false);
                selection.removeAllRanges();
                selection.addRange(range);
            }
        }
    }
    
    static _createRange(node, chars, range) {
        if (!range) {
            range = document.createRange()
            range.selectNode(node);
            range.setStart(node, 0);
        }

        if (chars.count === 0) {
            range.setEnd(node, chars.count);
        } else if (node && chars.count >0) {
            if (node.nodeType === Node.TEXT_NODE) {
                if (node.textContent.length < chars.count) {
                    chars.count -= node.textContent.length;
                } else {
                    range.setEnd(node, chars.count);
                    chars.count = 0;
                }
            } else {
                for (var lp = 0; lp < node.childNodes.length; lp++) {
                    range = Cursor._createRange(node.childNodes[lp], chars, range);

                    if (chars.count === 0) {
                    break;
                    }
                }
            }
        } 

        return range;
    }
    
    static _isChildOf(node, parentElement) {
        while (node !== null) {
            if (node === parentElement) {
                return true;
            }
            node = node.parentNode;
        }

        return false;
    }
}

如果你不想使用jQuery，你可以试试这个方法:

public setCaretPosition() {
    const editableDiv = document.getElementById('contenteditablediv');
    const lastLine = this.input.nativeElement.innerHTML.replace(/.*?(<br>)/g, '');
    const selection = window.getSelection();
    selection.collapse(editableDiv.childNodes[editableDiv.childNodes.length - 1], lastLine.length);
}

editableDiv你的可编辑元素，不要忘记为它设置一个id。然后你需要从元素中获取innerHTML并切断所有刹车线。然后用next参数设置collapse。

我正在编写一个语法高亮显示(和基本的代码编辑器)，我需要知道如何自动键入一个单引号字符并将插入符号移回(就像现在的许多代码编辑器一样)。

这里是我的解决方案的一个片段，感谢来自这个线程的帮助，MDN文档，和很多moz控制台观看。

//onKeyPress event

if (evt.key === "\"") {
    let sel = window.getSelection();
    let offset = sel.focusOffset;
    let focus = sel.focusNode;

    focus.textContent += "\""; //setting div's innerText directly creates new
    //nodes, which invalidate our selections, so we modify the focusNode directly

    let range = document.createRange();
    range.selectNode(focus);
    range.setStart(focus, offset);

    range.collapse(true);
    sel.removeAllRanges();
    sel.addRange(range);
}

//end onKeyPress event

这是一个可满足内容的div元素

我把这个留在这里作为感谢，意识到已经有一个公认的答案。

move(element:any,x:number){//parent
    let arr:Array<any>=[];
    arr=this.getAllnodeOfanItem(this.input.nativeElement,arr);
    let j=0;
    while (x>arr[j].length && j<arr.length){
        x-=arr[j].length;
        j++;
    }
    

    
    var el = arr[j];
    var range = document.createRange();
    var sel = window.getSelection();
    range.setStart(el,x );
    range.collapse(true);
    if (sel)sel.removeAllRanges();
    if (sel)sel.addRange(range);
}   

getAllnodeOfanItem(element:any,rep:Array<any>){
    let ch:Array<any>=element.childNodes;
    if (ch.length==0 && element.innerText!="")
        rep.push(element);
    else{
        for (let i=0;i<ch.length;i++){
            rep=this.getAllnodeOfanItem(ch[i],rep)
        }
    }
    return rep;
}

我为我的简单文本编辑器做了这个。

与其他方法的区别:

高性能 适用于所有空间

使用

// get current selection
const [start, end] = getSelectionOffset(container)

// change container html
container.innerHTML = newHtml

// restore selection
setSelectionOffset(container, start, end)

// use this instead innerText for get text with keep all spaces
const innerText = getInnerText(container)
const textBeforeCaret = innerText.substring(0, start)
const textAfterCaret = innerText.substring(start)

selection.ts

/** return true if node found */
function searchNode(
    container: Node,
    startNode: Node,
    predicate: (node: Node) => boolean,
    excludeSibling?: boolean,
): boolean {
    if (predicate(startNode as Text)) {
        return true
    }

    for (let i = 0, len = startNode.childNodes.length; i < len; i++) {
        if (searchNode(startNode, startNode.childNodes[i], predicate, true)) {
            return true
        }
    }

    if (!excludeSibling) {
        let parentNode = startNode
        while (parentNode && parentNode !== container) {
            let nextSibling = parentNode.nextSibling
            while (nextSibling) {
                if (searchNode(container, nextSibling, predicate, true)) {
                    return true
                }
                nextSibling = nextSibling.nextSibling
            }
            parentNode = parentNode.parentNode
        }
    }

    return false
}

function createRange(container: Node, start: number, end: number): Range {
    let startNode
    searchNode(container, container, node => {
        if (node.nodeType === Node.TEXT_NODE) {
            const dataLength = (node as Text).data.length
            if (start <= dataLength) {
                startNode = node
                return true
            }
            start -= dataLength
            end -= dataLength
            return false
        }
    })

    let endNode
    if (startNode) {
        searchNode(container, startNode, node => {
            if (node.nodeType === Node.TEXT_NODE) {
                const dataLength = (node as Text).data.length
                if (end <= dataLength) {
                    endNode = node
                    return true
                }
                end -= dataLength
                return false
            }
        })
    }

    const range = document.createRange()
    if (startNode) {
        if (start < startNode.data.length) {
            range.setStart(startNode, start)
        } else {
            range.setStartAfter(startNode)
        }
    } else {
        if (start === 0) {
            range.setStart(container, 0)
        } else {
            range.setStartAfter(container)
        }
    }

    if (endNode) {
        if (end < endNode.data.length) {
            range.setEnd(endNode, end)
        } else {
            range.setEndAfter(endNode)
        }
    } else {
        if (end === 0) {
            range.setEnd(container, 0)
        } else {
            range.setEndAfter(container)
        }
    }

    return range
}

export function setSelectionOffset(node: Node, start: number, end: number) {
    const range = createRange(node, start, end)
    const selection = window.getSelection()
    selection.removeAllRanges()
    selection.addRange(range)
}

function hasChild(container: Node, node: Node): boolean {
    while (node) {
        if (node === container) {
            return true
        }
        node = node.parentNode
    }

    return false
}

function getAbsoluteOffset(container: Node, offset: number) {
    if (container.nodeType === Node.TEXT_NODE) {
        return offset
    }

    let absoluteOffset = 0
    for (let i = 0, len = Math.min(container.childNodes.length, offset); i < len; i++) {
        const childNode = container.childNodes[i]
        searchNode(childNode, childNode, node => {
            if (node.nodeType === Node.TEXT_NODE) {
                absoluteOffset += (node as Text).data.length
            }
            return false
        })
    }

    return absoluteOffset
}

export function getSelectionOffset(container: Node): [number, number] {
    let start = 0
    let end = 0

    const selection = window.getSelection()
    for (let i = 0, len = selection.rangeCount; i < len; i++) {
        const range = selection.getRangeAt(i)
        if (range.intersectsNode(container)) {
            const startNode = range.startContainer
            searchNode(container, container, node => {
                if (startNode === node) {
                    start += getAbsoluteOffset(node, range.startOffset)
                    return true
                }

                const dataLength = node.nodeType === Node.TEXT_NODE
                    ? (node as Text).data.length
                    : 0

                start += dataLength
                end += dataLength

                return false
            })

            const endNode = range.endContainer
            searchNode(container, startNode, node => {
                if (endNode === node) {
                    end += getAbsoluteOffset(node, range.endOffset)
                    return true
                }

                const dataLength = node.nodeType === Node.TEXT_NODE
                    ? (node as Text).data.length
                    : 0

                end += dataLength

                return false
            })

            break
        }
    }

    return [start, end]
}

export function getInnerText(container: Node) {
    const buffer = []
    searchNode(container, container, node => {
        if (node.nodeType === Node.TEXT_NODE) {
            buffer.push((node as Text).data)
        }
        return false
    })
    return buffer.join('')
}