JavaScript drag and drop application examples (2)_javascript skills

I often see a drag-and-drop verification effect on the registration page of other websites. That is, the verification code does not come out at the beginning, but there is a drag-and-drop bar. You must drag this drag bar to the end. , the verification code just came out, and it feels the same as if I didn’t say it, but you still don’t understand, okay, let me give you a picture:

This is a picture taken from the registration page of Wanwang. The approximate effect is that when dragging the drag box, if the drag box is not dragged to the far right, the drag box will move to the initial position. , if you drag it to the far right, the drag box will be displayed as a check mark, and the text in the middle will also change, but I tried it, and his verification code box did not come out. I don’t know if it was changed or something, I didn’t Continue to click OK to proceed. That is not the focus of what we are talking about. I manually displayed the verification box in his code, which is the picture in the last few frames of the gif. In this way, you should understand what I want What do you mean? Yes, what we want to achieve today is the effect of drag and drop verification. We will not do the verification box after dragging

Look at the results we did:

The gif image feels a bit stuck. The actual effect should be smoother. I will see that the effect is basically the same. I won’t go into the specific implementation principles. If you don’t know how to implement it, you can go out and turn left to find An article I wrote: Javascript realizes the drag and drop effect in PC webpages. The writing is relatively clear. Master the basic principles of drag and drop to achieve such effects

That’s a piece of cake, haha, then I’ll post the code for everyone to see, for reference only:

css:

#drag_wrap{
  width:300px;
  height:35px;
  position:relative;
  background:#e8e8e8;
  margin:100px auto;
}
#drag_bg{
  width:0;
  height:35px;
  background:#7ac23c;
  position:absolute;
  top:0;
  left:0;
}
#drag_box{
  width:40px;
  height:33px;
  border:1px solid #ccc;
  background:#fff url(images/rt.png) no-repeat center center;
  position:absolute;
  top:0;
  left:0;
  cursor:move;
  z-index:2;
}
#drag_txt{
  width: 100%;
  height: 100%;
  text-align: center;
  position: absolute;
  z-index: 1;
  background: transparent;
  color: #9c9c9c;
  line-height: 35px;
  font-size: 12px;
}
#drag_txt span{
  cursor: default;
  z-index: 0;
}
#drag_txt .startTxt{
  background: -webkit-gradient(linear,left top,right top,color-stop(0,#4d4d4d),color-stop(.4,#4d4d4d),color-stop(.5,#fff),color-stop(.6,#4d4d4d),color-stop(1,#4d4d4d));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  -webkit-animation: slidetounlock 3s infinite;
  -webkit-text-size-adjust: none;
}
@-webkit-keyframes slidetounlock {
  0% {
    background-position: -200px 0
  }

  100% {
    background-position: 200px 0
  }
}
.yseTxt{
  background:none;
  color:#fff;
}

html:

<div id="drag_wrap">
    <div id="drag_bg"></div>
    <div id="drag_box"></div>
    <div id="drag_txt" ><span class="startTxt">请按住滑块，拖动到最右边</span></div>
  </div>

JavaScript:

window.onload = function(){

    drag("drag_box","drag_wrap","drag_bg","drag_txt");
    
    function drag(obj,parentNode,bgObj,oTxt,endFn){
      var obj = document.getElementById(obj);
      var parentNode = document.getElementById(parentNode);
      var bgObj = document.getElementById(bgObj);
      var oTxt = document.getElementById(oTxt);
      var aSpan = oTxt.getElementsByTagName("span")[0];
      obj.onmousedown = function(ev){
        var ev = ev || event;
        
        //非标准设置全局捕获(IE)
        if(obj.setCapture){
          obj.setCapture()  
        };

        var disX = ev.clientX - this.offsetLeft,
          disY = ev.clientY - this.offsetTop;
        var oWidth = obj.offsetWidth,
          oHeight = obj.offsetHeight;
        var pWidth = parentNode.offsetWidth,
          pHeight = parentNode.offsetHeight;      
        document.onmousemove = function(ev){
          var ev = ev || event;
          
          var left = ev.clientX - disX;
          //左侧
          if(left <= 0){
            left = 0;
          }else if(left >= pWidth - oWidth){//右侧
            left = pWidth - oWidth;
            obj.style.background = "#fff url(images/yes.png) no-repeat center center";
            aSpan.innerHTML = "验证通过"; //这里应该有ajax操作
            aSpan.className = 'yseTxt';
          };
          obj.style.left = bgObj.style.width = left + 'px';
    
          
        };
        document.onmouseup = function(ev){
          var ev = ev || event;
          document.onmousemove = document.onmouseup = null;
          //磁性吸附
          var L = ev.clientX - disX;
          if(L < pWidth - oWidth){
            startMove(obj,{left:0});
            startMove(bgObj,{width:0});  
          };
          endFn && endFn();
          //非标准释放全局捕获(IE)
          if(obj.releaseCapture){
            obj.releaseCapture()  
          };

        };
        return false;
      };  
    }  
    //这里是一个运动函数
    function startMove(obj,json,endFn){
      clearInterval(obj.timer);
      obj.timer = setInterval(function(){
        var bBtn = true;
        for(var attr in json){
          var iCur = 0;
          if(attr == 'opacity'){
            if(Math.round(parseFloat(getStyle(obj,attr))*100)==0){
              iCur = Math.round(parseFloat(getStyle(obj,attr))*100);
            }else{
              iCur = Math.round(parseFloat(getStyle(obj,attr))*100) || 100;
            }  
          }
          else{
            iCur = parseInt(getStyle(obj,attr)) || 0;
          }
          var iSpeed = (json[attr] - iCur)/5;
          iSpeed = iSpeed >0 &#63; Math.ceil(iSpeed) : Math.floor(iSpeed);
          if(iCur!=json[attr]){
            bBtn = false;
          }
          if(attr == 'opacity'){
            obj.style.filter = 'alpha(opacity=' +(iCur + iSpeed)+ ')';
            obj.style.opacity = (iCur + iSpeed)/100;  
          }
          else{
            obj.style[attr] = iCur + iSpeed + 'px';
          }
        }
        if(bBtn){
          clearInterval(obj.timer);
          if(endFn){
            endFn.call(obj);
          }
        }
      },30);
    }
    //这里是获取css样式函数
    function getStyle(obj,attr){
      if(obj.currentStyle){
        return obj.currentStyle[attr];  
      }else{
        return getComputedStyle(obj,false)[attr];
      }
    }

  }
 

Parameter description:

Five parameters are given here, obj, parentNode, bgObj, oTxt, endFn

obj: represents the drag object

parentNode: Represents the active area of ​​the drag object, usually set as the parent

bgObj: An object that represents the background color change when dragging

oTxt: Represents text change object

endFn: return function, optional

The above is the entire content of this article, I hope it will be helpful to everyone’s study.