WF规则设计器

WF规则设计器

WF的引擎提供了三种启动工作流的方法：

1. 指定引workFlow的类，这需要引用workFlow的DLL,或将workFlow与引擎放在同一个项目中
2. 指定引workFlow的xoml文件(动态编译)
3. 指定workFlow的xoml的字符串

这三种方式的例子我都写过，各自的优点我也说过，这里就不再描述了，

本例使用的是第三种，这种的好处是可将xoml字串存入数据库中，要修改流程可以直接对字符串操作，我的一个基于Visio开发的WF的设计器用的就是这种方式生

 

WF还提供了流程与规则相分离的方式，在启动流程时可以选择一个规则，这样就可以在不修改流程的情况下，通过使用为同的规则调整流程的条件轨迹

我以前的例子只提供了流程设计器，今天发一个规则设计器的例子

 

 

WF的规则与规则设计器类结构

 

 

例子:IfElseBranchActivity、WhileActivity、ConditionedActivityGroup、 ReplicatorActivity的规则编辑器

 

例子下载:http://files.cnblogs.com/wxwinter/WfEditRule.rar

 

创建一个工作流

 

将工作流的rules文件与xoml文件复制到[规则设计器]

 

启动一下看结果

 

修改规则

 

 

 

 

 

 

再启动一下看结果

 

规则设计器中操作规则的代码

//从字串得到rules字串得到RuleDefinitions private void button3_Click(object sender, EventArgs e) { System.Text.UTF8Encoding utf8 = new System.Text.UTF8Encoding();     byte[] a = utf8.GetBytes(this.rules.Text);   System.IO.MemoryStream m = new System.IO.MemoryStream(a);   XmlReader x = XmlReader.Create(m);   object objectRule = serializer.Deserialize(x);   ruleDefinitions = objectRule as RuleDefinitions; this.ruleslist.DisplayMember = "Name"; this.rulesSetlist.DisplayMember = "Name";     // Conditions中的CodeExpression列表 foreach (var v in ruleDefinitions.Conditions) { //添加到列表框 this.ruleslist.Items.Add(v); }     // RuleSets中的RuleSet列表 foreach (var v in ruleDefinitions.RuleSets) { //添加到列表框 this.rulesSetlist.Items.Add(v); } }

// 修改RuleDefinitions的Conditions的CodeExpression规则 private void button2_Click(object sender, EventArgs e) { RuleExpressionCondition ruleExpressionCondition = this.ruleslist.SelectedItem as RuleExpressionCondition; if (ruleExpressionCondition != null) { CodeExpression codeExpression = ruleExpressionCondition.Expression;     RuleConditionDialog ruleConditionDialog = new RuleConditionDialog(typeof(System.Workflow.ComponentModel.Activity), null, codeExpression);     if (ruleConditionDialog.ShowDialog() == System.Windows.Forms.DialogResult.OK) { CodeExpression expression = ruleConditionDialog.Expression; RuleExpressionCondition condition = new RuleExpressionCondition(expression); RuleValidation validation = new RuleValidation(typeof(System.Workflow.ComponentModel.Activity), null); if (condition.Validate(validation)) { ruleExpressionCondition.Expression = ruleConditionDialog.Expression; } else { Console.WriteLine("语法有错"); } }   } }

// 为RuleDefinitions的Conditions添加CodeExpression规则 private void button4_Click(object sender, EventArgs e) {   RuleConditionDialog ruleConditionDialog = new RuleConditionDialog(typeof(System.Workflow.ComponentModel.Activity), null, null);     if (ruleConditionDialog.ShowDialog() == System.Windows.Forms.DialogResult.OK) { CodeExpression expression = ruleConditionDialog.Expression; RuleExpressionCondition condition = new RuleExpressionCondition(expression); RuleValidation validation = new RuleValidation(typeof(System.Workflow.ComponentModel.Activity), null); if (condition.Validate(validation)) { condition.Name = this.newRulesName.Text; this.ruleslist.Items.Add(condition);   } else { Console.WriteLine("语法有错"); } } }

//保存RuleDefinitions到字串得到rules字串得 private void button5_Click(object sender, EventArgs e) {   WorkflowMarkupSerializer serializer = new WorkflowMarkupSerializer();   System.IO.MemoryStream stream=new System.IO.MemoryStream();       XmlTextWriter writer = new XmlTextWriter(stream, null);   serializer.Serialize(writer, ruleDefinitions); writer.Flush();   byte[] by;   by = stream.GetBuffer(); System.Text.UTF8Encoding utf8 = new System.Text.UTF8Encoding(); string s = utf8.GetString(by); writer.Close();   this.rules.Text = s;   }