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:https://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;

 

}