Html 画布中的对象定义

我在大学最后一年做了一个名为“数据流图绘制工具”的期末项目，它是基于网站的。当画布中的图表出现错误时，我很难做出警告。例如，终止符满足数据流，然后满足流程是正确的。但当终止符遇到数据流，然后遇到存储时，则是错误的。发生此错误时，我如何发出警告？显然，我需要画布中每个形状的某种对象定义。我该怎么做？我真的需要帮助：（

以下是如何创建和验证数据流步骤的快速概述：

// create javascript objects representing data-flow steps
// and put the steps objects in an array for easy processing
var steps=[];
steps.push({type:'External',label:'Customer'});
steps.push({type:'Flow',label:'Place Order',isBidirectional:true});
steps.push({type:'Process',label:'Process Order'});
steps.push({type:'Flow',label:'Save Order',isBidirectional:false});
steps.push({type:'Storage',label:'DB Table: Orders'});

// start out assuming all steps are valid
for(var i=1;i<steps;i++){ steps[i].isValid=true; }

// look for invalid steps and mark them
// This example checks for sequential steps not separated by flows
for(var i=1;i<steps;i++){
    if(steps[i-1].type!=='Flow' && steps[i].type!=='Flow){
        steps[i].isValid=false;
    }
}

• 创建JavaScript对象以保存与数据流图中每个步骤相关的信息

• 将所有步骤对象保存在一个数组中，以便于处理

• 迭代步骤数组并验证每个步骤

示例代码：

// create javascript objects representing data-flow steps
// and put the steps objects in an array for easy processing
var steps=[];
steps.push({type:'External',label:'Customer'});
steps.push({type:'Flow',label:'Place Order',isBidirectional:true});
steps.push({type:'Process',label:'Process Order'});
steps.push({type:'Flow',label:'Save Order',isBidirectional:false});
steps.push({type:'Storage',label:'DB Table: Orders'});

// start out assuming all steps are valid
for(var i=1;i<steps;i++){ steps[i].isValid=true; }

// look for invalid steps and mark them
// This example checks for sequential steps not separated by flows
for(var i=1;i<steps;i++){
    if(steps[i-1].type!=='Flow' && steps[i].type!=='Flow){
        steps[i].isValid=false;
    }
}

//创建表示数据流步骤的javascript对象
//并将步骤对象放入数组中，以便于处理
var步骤=[]；
push（{类型：'External'，标签：'Customer'}）；
push（{type:'Flow'，label:'placeorder'，isdirectional:true}）；
push（{类型：'Process'，标签：'processorder'}）；
push（{type:'Flow'，label:'Save Order'，isdirectional:false}）；
push（{type:'Storage'，label:'DB Table:Orders'}）；
//假设所有步骤都有效就开始
对于（var i=1；i