1.初次实现
1.1 html代码
<html xmlns="www.w3.org/1999/xhtml" xml:lang="en" lang="en"><head><meta http-equiv="content-type" content="text/html; charset=utf-8" /><title>div change width by drag</title><script src="../jquery/jquery-1.8.3.min.js?1.1.11" type="text/javascript"></script></head><body><h1>div change width by drag</h1><div id="pos" style="color:red"></div><div id="mydiv" style="border:2px solid red;width:300px;height:50px;margin-left: 100px;margin-top: 20px"></div></body></html>
1.2 js代码
var eleleft = $('#mydiv').offset().left;var ismousedown = false;var borderlen = 4; //左右边框
$('#mydiv').bind({
mousedown:function(e){var ele = $(this);var rightpos = eleleft + ele.width() + borderlen;if(rightpos-5 <= e.pagex && e.pagex <= rightpos){
ismousedown = true;
}
},
mousemove:function(e){var ele = $(this);var rightpos = eleleft + ele.width() + borderlen;
$('#pos').text("x:"+e.pagex + " eleleft:"+eleleft+" rightpos:"+rightpos);if(rightpos-5 <= e.pagex && e.pagex <= rightpos){
ele.css('cursor','e-resize');
}else{if(!ismousedown){
ele.css('cursor','auto');
}
}if(ismousedown){
ele.width((e.pagex-eleleft-borderlen)+'px'); //新鼠标位置-div距左-borderlen }
},
mouseup:function(e){
ismousedown = false;
}
});
1.3 结果
只能往左拖动使div宽度变小，往右拖动没有用！原因往右拖动鼠标mousemove事件无法被div捕获了。拖动时也很难停下来！所以得改进。
2.再次改进
$('#mydiv' ele = $( rightpos = eleleft + ele.width() +(rightpos-5 <= e.pagex && e.pagex <== 'body' ele = $('#mydiv' rightpos = eleleft + ele.width() +'#pos').text("x:"+e.pagex + " eleleft:"+eleleft+" rightpos:"+(rightpos-5 <= e.pagex && e.pagex <='cursor','e-resize'(!'cursor','auto'-eleleft-borderlen)+'px'); =
这次解决了上述问题，可以往右拖，并且随时可以停下来了。到这里就完成了吗？no!
当我引入一个其他div，并且阻止mouseup事件冒泡情况怎么样呢？答案是，拖动到这个其它div上放开鼠标后无法停止下来！
<div id="otherdiv" style="border: 2px solid blue;width: 200px;height: 200px;margin-left: 400px"></div>
$('#otherdiv').mouseup(function(e){//e.preventdefault(); //阻止默认行为e.stoppropagation(); //阻止事件冒泡(导致body捕获不到mouseup事件)});
3.完美解决
拖动停止可能受到其它元素的干扰，怎么解决？想到一些弹出层点击其它其它地方隐藏的功能，让我想到了，加一个遮罩层，让mouseup事件总是可以响应，不就搞定了嘛！
$('#mydiv').bind({
mousedown:function(e){var ele = $(this);var rightpos = eleleft + ele.width() + borderlen;if(rightpos-5 <= e.pagex && e.pagex <= rightpos){
ismousedown = true;//创建遮罩层，防止mouseup事件被其它元素阻止冒泡，导致mouseup事件无法被body捕获，导致拖动不能停止var bodywidth = $('body').width();var bodyheight = $('body').height();
$('body').append('<div id="mask" style="opacity:0.2;top:0px;left:0px;background-color:green;position:absolute;z-index:9999;width:'+bodywidth+'px;height:'+bodyheight+'px;"></div>');
}
}
});
$('body').bind({
mousemove:function(e){var ele = $('#mydiv');var rightpos = eleleft + ele.width() + borderlen;
$('#pos').text(x:+e.pagex + eleleft:+eleleft+ rightpos:+rightpos);if(rightpos-5 <= e.pagex && e.pagex <= rightpos){
ele.css('cursor','e-resize');
}else{if(!ismousedown){
ele.css('cursor','auto');
}
}if(ismousedown){
ele.width((e.pagex-eleleft-borderlen)+'px');
}
},
mouseup:function(e){
ismousedown = false;
$('#mask').remove();
}
});
$('#otherdiv').mouseup(function(e){//e.preventdefault(); //阻止默认行为e.stoppropagation(); //阻止事件冒泡(导致body捕获不到mouseup事件)});
4.完整代码和最终效果
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en"><head><meta http-equiv="content-type" content="text/html; charset=utf-8" /><title>div change width by drag</title><script src="../jquery/jquery-1.8.3.min.js?1.1.11" type="text/javascript"></script>
</head><body><h1>div change width by drag</h1><div id="pos" style="color:red"></div>
<div id="mydiv" style="border:2px solid red;width:300px;height:50px;margin-left: 100px;margin-top: 20px"></div><div id="otherdiv" style="border: 2px solid blue;width: 200px;height: 200px;margin-left: 400px"></div></body><script type="text/javascript">$(document).ready(function(){var eleleft = $('#mydiv').offset().left;var ismousedown = false;var borderlen = 4; //左右边框$('#mydiv').bind({
mousedown:function(e){var ele = $(this);var rightpos = eleleft + ele.width() + borderlen;if(rightpos-5 <= e.pagex && e.pagex <= rightpos){
ismousedown = true;//创建遮罩层，防止mouseup事件被其它元素阻止冒泡，导致mouseup事件无法被body捕获，导致拖动不能停止var bodywidth = $('body').width();var bodyheight = $('body').height();
$('body').append('<div id="mask" style="opacity:0.2;top:0px;left:0px;background-color:green;position:absolute;z-index:9999;width:'+bodywidth+'px;height:'+bodyheight+'px;"></div>');
}
}
});
$('body').bind({
mousemove:function(e){var ele = $('#mydiv');var rightpos = eleleft + ele.width() + borderlen;
$('#pos').text(x:+e.pagex + eleleft:+eleleft+ rightpos:+rightpos);if(rightpos-5 <= e.pagex && e.pagex <= rightpos){
ele.css('cursor','e-resize');
}else{if(!ismousedown){
ele.css('cursor','auto');
}
}if(ismousedown){
ele.width((e.pagex-eleleft-borderlen)+'px'); }
},
mouseup:function(e){
ismousedown = false;
$('#mask').remove();
}
});
$('#otherdiv').mouseup(function(e){//e.preventdefault(); //阻止默认行为 e.stoppropagation(); //阻止事件冒泡(导致body捕获不到mouseup事件) });
});</script></html>
以上就是鼠标拖动改变div的实例详解的详细内容。