最开始使用的 vue-code-dff 插件  有坑 直接导致页面卡死  所以改用下面得插件

1、首先安装插件

npm install codemirror、diff-match-patch

2、二话不说 直接键个vue 文件   上代码

<template>
    <div class="compareClass">
        <!-- 代码版本，差异对比 对话框内容 -->
        <div id="view" style="margin-top:10px"></div>
    </div>
</template>

<script>
    // 引入全局实例
    import CodeMirror from 'codemirror'
    // 核心样式
    import 'codemirror/lib/codemirror.css'
    // 引入主题后还需要在 options 中指定主题才会生效
    import 'codemirror/theme/idea.css'

    // 需要引入具体的语法高亮库才会有对应的语法高亮效果
    // codemirror 官方其实支持通过 /addon/mode/loadmode.js 和 /mode/meta.js 来实现动态加载对应语法高亮库
    // 但 vue 貌似没有无法在实例初始化后再动态加载对应 JS ，所以此处才把对应的 JS 提前引入
    import 'codemirror/mode/javascript/javascript.js'
    import 'codemirror/mode/css/css.js'
    import 'codemirror/mode/xml/xml.js'
    import 'codemirror/mode/shell/shell.js'
    import 'codemirror/mode/sql/sql.js'

    //代码补全提示
    import 'codemirror/addon/hint/anyword-hint.js';
    import 'codemirror/addon/hint/css-hint.js';
    import 'codemirror/addon/hint/html-hint.js';
    import 'codemirror/addon/hint/javascript-hint.js';
    import 'codemirror/addon/hint/show-hint.css';
    import 'codemirror/addon/hint/show-hint.js';
    import 'codemirror/addon/hint/sql-hint.js';
    import 'codemirror/addon/hint/xml-hint.js';

    //代码版本差异比较
    import 'codemirror/addon/merge/merge.js'
    import 'codemirror/addon/merge/merge.css'
    import DiffMatchPatch from 'diff-match-patch'

    window.diff_match_patch = DiffMatchPatch
    window.DIFF_DELETE = -1
    window.DIFF_INSERT = 1
    window.DIFF_EQUAL = 0

    export default {
        name: "Code",
        data() {
            return {
            }
        },

        created() {
        },
        mounted() {
            this.$nextTick(() => {
                this.initUI()
            })
        },
        methods: {
            // 初始化
            initUI() {
                let target = document.getElementById("view");
                target.innerHTML = "";
                CodeMirror.MergeView(target, {
                    value: "/*以下为演示内容，请添加您自己的内容 ~_~ */\n" +
                        "\n" +
                        "html,\n" +
                        "body {\n" +
                        "  width: 100%;\n" +
                        "  height: 100%;\n" +
                        "  margin: 0;\n" +
                        "  padding: 0;\n" +
                        "  overflow: hidden;\n" +
                        "  font-family: 'Fira Mono', helvetica, arial, sans-serif;\n" +
                        "  font-weight: 400;\n" +
                        "  font-size: 62.5%;\n" +
                        "}\n" +
                        "\n" +
                        "#webgl-container {\n" +
                        "  width: 100%;\n" +
                        "  height: 100%;\n" +
                        "  cursor: pointer;\n" +
                        "}\n" +
                        "\n" +
                        ".loading {\n" +
                        "  position: absolute;\n" +
                        "  width: 100%;\n" +
                        "  height: 100%;\n" +
                        "  background-color: #000000;\n" +
                        "  opacity: 1;\n" +
                        "  -webkit-transition: opacity 1.2s ease-out;\n" +
                        "  -o-transition: opacity 1.2s ease-out;\n" +
                        "  transition: opacity 1.2s ease-out;\n" +
                        "  pointer-events: none;\n" +
                        "  z-index: 5;" +
                        "}", //上次内容
                    origLeft: null,
                    orig: ".dialog-footwer {\n" +
                        "  text-align: center;\n" +
                        "  margin-top: 20px;\n" +
                        "}\n" +
                        "\n" +
                        ".toggle_wrap {\n" +
                        "  margin-bottom: 6px;\n" +
                        "  height: auto;\n" +
                        "  overflow-y: auto;\n" +
                        "}\n" +
                        ".toggle_wrap_card {\n" +
                        "  padding: 0 10px 10px 10px;\n" +
                        "}\n" +
                        "\n" +
                        "/deep/.el-button--success {\n" +
                        "  background-color: transparent;\n" +
                        "  border-color: #5bacff;\n" +
                        "  color: #5bacff;\n" +
                        "}\n" +
                        "</style>", //本次内容
                    lineNumbers: true, //显示行号
                    smartIndent: true, //自动缩进是否开启\
                    indentUnit: 2,
                    mode: "shell",
                    highlightDifferences: true,
                    styleActiveLine: true,
                    matchBrackets: true,
                    connect: 'align',
                    theme: 'cobalt',
                    readOnly: true, //只读 不可修改
                });
            },
        }
    };
</script>
<style lang="scss" scode>
    .compareClass {
        height: 900px;
        overflow-y: hidden;
        overflow-x: auto;

        /deep/.CodeMirror-merge,
        .CodeMirror-merge .CodeMirror {
            height: 680px;
            overflow-y: hidden;
        }
    }
</style>

3. 效果