前端滑动验证码

效果：

完整源码：

<template>
    <div class="flex-center">
        <div id="dragContainer">
           <!-- 绿色区域 -->
           <div id="dragBg"></div>
           <!-- 滑动容器文本 -->
           <div id="dragText"></div>
           <!-- 拖动元素 -->
           <div id="dragHandler" class="dragHandlerBg"></div>
        </div>
        <div class="btn" @click="initDrag">初始化</div>
    </div>
</template>
<script>
    export default {
        data() {
            return {
              dragContainer: null,
              dragBg: null,
              dragText: null,
              dragHandler: null,
              maxHandlerOffset: null,
            }
        },
        mounted() {
            //获取滑动控件容器,灰色背景
            this.dragContainer = document.getElementById("dragContainer");
            //获取滑块左边部分,绿色背景
            this.dragBg = document.getElementById("dragBg");
            //获取滑动验证容器文本
            this.dragText = document.getElementById("dragText");
            //获取滑块
            this.dragHandler = document.getElementById("dragHandler");
            //滑块的最大偏移量 = 滑动验证容器文本长度 - 滑块长度
            this.maxHandlerOffset = dragContainer.clientWidth - dragHandler.clientWidth;
            // 初始化
            this.initDrag();
        },
        methods: {
            // 初始化
            initDrag() {
                //在滑动验证容器文本写入“拖动滑块验证”
                this.dragText.textContent = "拖动滑块验证";
                //给滑块添加鼠标按下监听
                this.dragHandler.addEventListener("mousedown", this.onDragHandlerMouseDown);
                //初始化滑块移动量
                this.dragHandler.style.left = 0;
                //初始化绿色背景
                this.dragBg.style.width = 0;
                this.dragText.style.color = "";
                this.dragHandler.setAttribute("class", "dragHandlerBg");
            },
            // 鼠标按下
            onDragHandlerMouseDown() {
                //鼠标移动监听
                document.addEventListener("mousemove", this.onDragHandlerMouseMove);
                //鼠标松开监听
                document.addEventListener("mouseup",  this.onDragHandlerMouseUp);
            },
            // 鼠标移动
            onDragHandlerMouseMove() {
                //滑块移动量
                let dragX = this.dragBg?.getBoundingClientRect()||{}
                var left = event.clientX - this.dragHandler.clientWidth / 2 - dragX.left;
                
                if(left < 0) { // 滑动小于0设为0
                    left = 0;
                } else if(left >= this.maxHandlerOffset) { // 滑动超过最大偏移量则校验成功
                    left = this.maxHandlerOffset;
                    this.verifySucc();
                }
                // 超过最大偏移量，不增加绿色区域宽度
                if(left>this.maxHandlerOffset) return;
                // 滑块移动量（距离左侧的定位）
                this.dragHandler.style.left = left + "px";
                // 绿色背景的长度
                this.dragBg.style.width = left + "px";
            },
            // 鼠标抬起
            onDragHandlerMouseUp() {
                //移除鼠标移动监听
                document.removeEventListener("mousemove", this.onDragHandlerMouseMove);
                //移除鼠标松开监听
                document.removeEventListener("mouseup", this.onDragHandlerMouseUp);
                //初始化滑块移动量
                this.dragHandler.style.left = 0;
                //初始化绿色背景
                this.dragBg.style.width = 0;
            },
            // 滑动完成
            verifySucc() {
                //容器文本的文字改为白色“验证通过”字体
                this.dragText.textContent = "验证通过";
                this.dragText.style.color = "white";
                //验证通过的滑块背景
                this.dragHandler.setAttribute("class", "dragHandlerOkBg");
                //移除鼠标按下监听
                this.dragHandler.removeEventListener("mousedown", this.onDragHandlerMouseDown);
                //移除 鼠标移动监听
                document.removeEventListener("mousemove", this.onDragHandlerMouseMove);
                //移除鼠标松开监听
                document.removeEventListener("mouseup", this.onDragHandlerMouseUp);
                // alert('操作成功')
            },
        }
    }
</script>
 
<style>
.flex-center {
    display: flex;
    align-items: center;
}
.btn {
    border: 1px solid blue;
    width: 60px;
    text-align: center;
    color: blue;
    height: 33px;
    line-height: 33px;
    margin-left: 15px;
    cursor: pointer;
}
/* 滑动控件容器,灰色背景 */
#dragContainer {
    position: relative;
    display: inline-block;
    background: #e8e8e8;
    width: 300px;
    height: 33px;
    border: 2px solid #e8e8e8;
}
/* 滑块左边部分,绿色背景 */
#dragBg {
    position: absolute;
    background-color: #7ac23c;
    width: 0px;
    height: 100%;
}
/* 滑动验证容器文本 */
#dragText {
    position: absolute;
    width: 100%;
    height: 100%;
    /* 文字水平居中 */
    text-align: center;
    /* 文字垂直居中,这里不能用百分比,因为百分比是相对原始line-height的,而非div高度 */
    line-height: 33px;
    /* 文本不允许选中 */
    user-select: none;
    -webkit-user-select: none;
}
/* 滑块 */
#dragHandler {
    position: absolute;
    width: 40px;
    height: 100%;
    cursor: move;
}
/* 滑块初始背景 */
.dragHandlerBg {
    background: #fff no-repeat center url("data:image/png;base64,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");
}
/* 验证成功时的滑块背景 有√*/
.dragHandlerOkBg {
    background: #fff no-repeat center url("data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABAAAAAQCAYAAAAf8/9hAAAAGXRFWHRTb2Z0d2FyZQBBZG9iZSBJbWFnZVJlYWR5ccllPAAAA3hpVFh0WE1MOmNvbS5hZG9iZS54bXAAAAAAADw/eHBhY2tldCBiZWdpbj0i77u/IiBpZD0iVzVNME1wQ2VoaUh6cmVTek5UY3prYzlkIj8+IDx4OnhtcG1ldGEgeG1sbnM6eD0iYWRvYmU6bnM6bWV0YS8iIHg6eG1wdGs9IkFkb2JlIFhNUCBDb3JlIDUuNS1jMDIxIDc5LjE1NTc3MiwgMjAxNC8wMS8xMy0xOTo0NDowMCAgICAgICAgIj4gPHJkZjpSREYgeG1sbnM6cmRmPSJodHRwOi8vd3d3LnczLm9yZy8xOTk5LzAyLzIyLXJkZi1zeW50YXgtbnMjIj4gPHJkZjpEZXNjcmlwdGlvbiByZGY6YWJvdXQ9IiIgeG1sbnM6eG1wTU09Imh0dHA6Ly9ucy5hZG9iZS5jb20veGFwLzEuMC9tbS8iIHhtbG5zOnN0UmVmPSJodHRwOi8vbnMuYWRvYmUuY29tL3hhcC8xLjAvc1R5cGUvUmVzb3VyY2VSZWYjIiB4bWxuczp4bXA9Imh0dHA6Ly9ucy5hZG9iZS5jb20veGFwLzEuMC8iIHhtcE1NOk9yaWdpbmFsRG9jdW1lbnRJRD0ieG1wLmRpZDo0ZDhlNWY5My05NmI0LTRlNWQtOGFjYi03ZTY4OGYyMTU2ZTYiIHhtcE1NOkRvY3VtZW50SUQ9InhtcC5kaWQ6NDlBRDI3NjVGMkQ2MTFFNEI5NDBCMjQ2M0ExMDQ1OUYiIHhtcE1NOkluc3RhbmNlSUQ9InhtcC5paWQ6NDlBRDI3NjRGMkQ2MTFFNEI5NDBCMjQ2M0ExMDQ1OUYiIHhtcDpDcmVhdG9yVG9vbD0iQWRvYmUgUGhvdG9zaG9wIENDIDIwMTQgKE1hY2ludG9zaCkiPiA8eG1wTU06RGVyaXZlZEZyb20gc3RSZWY6aW5zdGFuY2VJRD0ieG1wLmlpZDphNWEzMWNhMC1hYmViLTQxNWEtYTEwZS04Y2U5NzRlN2Q4YTEiIHN0UmVmOmRvY3VtZW50SUQ9InhtcC5kaWQ6NGQ4ZTVmOTMtOTZiNC00ZTVkLThhY2ItN2U2ODhmMjE1NmU2Ii8+IDwvcmRmOkRlc2NyaXB0aW9uPiA8L3JkZjpSREY+IDwveDp4bXBtZXRhPiA8P3hwYWNrZXQgZW5kPSJyIj8+k+sHwwAAASZJREFUeNpi/P//PwMyKD8uZw+kUoDYEYgloMIvgHg/EM/ptHx0EFk9I8wAoEZ+IDUPiIMY8IN1QJwENOgj3ACo5gNAbMBAHLgAxA4gQ5igAnNJ0MwAVTsX7IKyY7L2UNuJAf+AmAmJ78AEDTBiwGYg5gbifCSxFCZoaBMCy4A4GOjnH0D6DpK4IxNSVIHAfSDOAeLraJrjgJp/AwPbHMhejiQnwYRmUzNQ4VQgDQqXK0ia/0I17wJiPmQNTNBEAgMlQIWiQA2vgWw7QppBekGxsAjIiEUSBNnsBDWEAY9mEFgMMgBk00E0iZtA7AHEctDQ58MRuA6wlLgGFMoMpIG1QFeGwAIxGZo8GUhIysmwQGSAZgwHaEZhICIzOaBkJkqyM0CAAQDGx279Jf50AAAAAABJRU5ErkJggg==");
}
</style>