系列1、2中介绍过的内容在这里不会赘述。
原理同面1、2基本一样。

<! DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd" >
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< html xmlns ="http://www.w3.org/1999/xhtml" >
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< head >
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< meta http-equiv ="Content-Type" content ="text/html; charset=utf-8" />
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< title > TEST </ title >
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< script type ="text/javascript" src ="wz_jsgraphics.js" ></ script >
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< script type ="text/javascript" src ="line.js" ></ script >
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</ head >
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< body >
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< p > 1.线图 </ p >
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< div id ="LineDiv" style ="position:relative;height:200px;width:300px;" ></ div >
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< script language ="javascript" >
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var y = new Array ();
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y[ 0 ] = 16000 ;
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y[ 1 ] = 1000 ;
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y[ 2 ] = 20000 ;
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y[ 3 ] = 100 ;
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y[ 4 ] = - 500 ;
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y[ 5 ] = 9000 ;
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var x = new Array ();
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x[ 0 ] = " a " ;
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x[ 1 ] = " b " ;
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x[ 2 ] = " c " ;
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x[ 3 ] = " aa " ;
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x[ 4 ] = " bb " ;
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x[ 5 ] = " dd " ;
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var myline = new Line( " LineDiv " );
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myline.drawXYLine(y,x);
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// myline.clearLine();
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</ script >
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</ body >
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</ html >

效果图：

/* ************更多技术文章请访问：http://www.blogjava.net/JAVA-HE****************
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*
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* 文件名：line.js V 1.01
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*
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* 作者：何昌敏
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*
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* 时间：2007-7
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*
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* 描述：绘制坐标曲线图
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*
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* 备注：
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* 1.实现了根据所提供数据，自动标刻y轴坐标。
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* 2.实现了图像清除。
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* 3.调整startx starty能实现整体位置调整。
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*
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* 感谢：Walter Zorn提供了API ——wz_jsgraphics.js v. 3.01。
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*
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*************更多技术文章请访问：http://www.blogjava.net/JAVA-HE*************** */
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function Line(obj)
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{
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this .jg = new jsGraphics(obj);
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var colors = new Array();
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colors[ 0 ] = " #0066FF " ;
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colors[ 1 ] = " #FF6633 " ;
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colors[ 2 ] = " #9900FF " ;
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colors[ 3 ] = " #FF0066 " ;
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colors[ 4 ] = " #066600 " ;
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colors[ 5 ] = " #006633 " ;
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colors[ 6 ] = " #33FFFF " ;
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colors[ 7 ] = " #000000 " ;
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colors[ 8 ] = " #FFFF00 " ;
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colors[ 9 ] = " #000033 " ;
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colors[ 10 ] = " #CCFFFF " ;
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colors[ 11 ] = " #666666 " ;
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this .start_x = 40 ; // 应大于等于y_str_width
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this .y_str_width = 40 ; // 坐标系的左边距
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this .x_str_tom = 10 ; // x轴文字距离坐标系底部距离。
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this .start_y = 20 ; // >=this.ArrowLength*2 箭头的高度
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this .width = 200 ;
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this .height = 120 ;
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this .y_line_num = 5 ;
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this .IsDrawArrow = true ;
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this .ArrowLength = 6 ;
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this .drawXYLine = function (_y,_x)
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{
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var y_length = _y.length;
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var x_length = _x.length;
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if (y_length != x_length)
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{
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alert( " X and Y length of inconsistencies, errors parameters. " );
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return ;
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}
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var y_line_distance = Math.round( this .height / this .y_line_num);
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var x_line_distance = Math.round( this .width / x_length);
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this .jg.drawLine( this .start_x, this .start_y + this .height, this .start_x + this .width, this .start_y + this .height); // x
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this .jg.drawLine( this .start_x, this .start_y + this .height, this .start_x, this .start_y); // y
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this .jg.setStroke(Stroke.DOTTED);
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var _y_copy = _y.concat();
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var temp = _y;
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temp.sort( function AscSort(x, y)
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{
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return x == y ? 0 : (x > y ? 1 : - 1 );
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}
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);
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var y_max2y_min = temp[x_length - 1 ] - temp[ 0 ];
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var y_min = temp[ 0 ];
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var y_value_distance = y_max2y_min / this .y_line_num;
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for ( var i = 0 ;i < this .y_line_num;i ++ )
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{
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var y_item = this .start_y + this .height - (i + 1 ) * y_line_distance;
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this .jg.drawLine( this .start_x,y_item, this .start_x + this .width,y_item);
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var y_v = Math.round(y_value_distance * (i + 1 ) + y_min);
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this .jg.drawString(y_v, this .start_x - this .y_str_width,y_item);
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}
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for (i = 0 ;i < x_length;i ++ )
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{
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this .jg.setStroke( - 1 );
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this .jg.setColor( " #000000 " );
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var x_item_end = this .start_x + x_line_distance * (i + 1 );
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this .jg.drawLine(x_item_end, this .start_y + this .height,x_item_end, this .start_y);
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this .jg.drawString(_x[i],x_item_end, this .start_y + this .height + 10 );
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}
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for (i = y_length;i > 1 ;i -- )
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{
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this .jg.setStroke( 2 );
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this .jg.setColor( " #FF0000 " );
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var x_temp_1 = this .start_x + x_line_distance * (i);
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var x_temp_2 = this .start_x + x_line_distance * (i - 1 );
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// alert(_y_copy[i-1]);
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// alert(y_min);
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// alert(y_max2y_min);
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var y_temp_1 = Math.round( this .height - this .height * (_y_copy[i - 1 ] - y_min) / y_max2y_min + this .start_y);
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var y_temp_2 = Math.round( this .height - this .height * (_y_copy[i - 2 ] - y_min) / y_max2y_min + this .start_y);
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this .jg.drawLine(x_temp_1,y_temp_1,x_temp_2,y_temp_2);
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}
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if ( this .IsDrawArrow)
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{
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this .jg.setStroke( 1 );
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this .jg.setColor( " #000000 " );
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this .jg.drawLine( this .start_x - this .ArrowLength, this .start_y, this .start_x, this .start_y - 2 * this .ArrowLength);
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this .jg.drawLine( this .start_x + this .ArrowLength, this .start_y, this .start_x, this .start_y - 2 * this .ArrowLength);
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this .jg.drawLine( this .start_x, this .start_y, this .start_x, this .start_y - 2 * this .ArrowLength);
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this .jg.drawLine( this .start_x + this .width, this .start_y + this .height - this .ArrowLength, this .start_x + this .width + 2 * this .ArrowLength, this .start_y + this .height);
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this .jg.drawLine( this .start_x + this .width, this .start_y + this .height + this .ArrowLength, this .start_x + this .width + 2 * this .ArrowLength, this .start_y + this .height);
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this .jg.drawLine( this .start_x + this .width, this .start_y + this .height, this .start_x + this .width + 2 * this .ArrowLength, this .start_y + this .height);
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}
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this .jg.paint();
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} ;
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this .clearLine = function ()
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{
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this .jg.clear();
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} ;
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}

总结遇到过的一些问题，一数组排序
总结如下：
http://www.blogjava.net/JAVA-HE/archive/2007/07/01/127304.html

二数组排序后怎么取原来没有排序的数组
eg：

< html >
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< body >
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< script type ="text/javascript" >
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function AscSort(x, y) {
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return x == y ? 0 : (x > y ? 1 : - 1 );
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}
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var y = new Array( 36000 , 200 , 500 , 10100 );
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var te = y;
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te.sort(AscSort);
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alert(te);
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alert(y);
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</ script >
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</ body >
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</ html >

如上程序，我对数组te排序了。但是我又要用到没有排序的数组y，但是程序的结果是y也排序了。有什么方法吗？
问题解决：利用concat方法，实现了数组的拷贝。

后记：这种方式的确实现了将数据库中动态数据以图表形式显示在页面上。程序以javascript实现，利用ajax将实现更好的用户体验。这样做减轻了服务端的压力。不过，这种方式的确定是客户端变得庞大。而且其实现原理很恐怖，基本是div实现点阵字原理（一点点画上去的）来搞的。效率就显得不够快。不过我在项目用这中方式也做完一个项目了。呵呵，和原来用jfreechart比较，感觉jfreechart （当然完全可以利用cewolf来简化操作）不爽的地方是他总是先生成图。然后利用src来显示的。其实效率也不怎么高。不过服务器好的话，客户端就轻松。无非就是胖客户端和胖服务器的比较，立场都不同了。

程序内部注释较少，代码很少。

posted on 2007-07-01 04:31 -274°C 阅读(9896) 评论(11) 编辑收藏

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