WF:关于流程设计器的一点补充

最近不少朋友对我以前发的一些例子中的流程设计器有一些疑问，以后我会专门写一个流程设计器的例子,这里先写几个开发流程设计器时要用到的小知识点

1.为自定义的Activity添加图标



为自定义Activity设置成员属性


[System.Drawing.ToolboxBitmap(typeof(wxdActivity), "wxd.bmp")]


public class wxdActivity : System.Workflow.ComponentModel.Activity
2.为Activity设置外观


//设计器样式类


[ActivityDesignerThemeAttribute(typeof(wxdTheme))]


public class wxdActivityDesigner : ActivityDesigner






{


}




//主题类


public class wxdTheme : ActivityDesignerTheme






{


public wxdTheme(WorkflowTheme theme)


: base(theme)






{


this.BorderColor = Color.Red; //边框色


this.BorderStyle = DashStyle.Dash ; //边框线条


this.BackColorStart = Color.White; //渐变开始色


this.BackColorEnd = Color.Blue; //渐变结束色


this.BackgroundStyle = LinearGradientMode.ForwardDiagonal;//渐变方向




}


}
为自定义Activity设置成员属性


[Designer(typeof(wxdActivityDesigner), typeof(IDesigner))]


public class wxdActivity : System.Workflow.ComponentModel.Activity

如果在继承了SequenceActivity的Activity使用了上面方式定义的主题，可以使用其内部Activity结构不显示,有时不想在流程设计器中对用户暴露太多信息可以用这个方法



3.为Activity添加右键菜单与数据绑定窗体
有时使用属性栏对Activity进行设置，对用户来说不是很方便，比如有些属性值是用户名，设备名等要从数据库中动态加载的数据，这时为最好提供一个数据绑定窗体向导


using System.Workflow.ComponentModel;


using System.ComponentModel;


using System.Workflow.ComponentModel.Design;


using System.Drawing;


using System.Drawing.Drawing2D;


using System.ComponentModel.Design;


using System;


using System.Collections.Generic;


namespace wxwinter






{




//自定义Activity


[Designer(typeof(wxdActivityDesigner), typeof(IDesigner))]


public class wxdActivity : System.Workflow.ComponentModel.Activity






{


public static DependencyProperty wxdValueProperty =




DependencyProperty.Register("wxdValue", typeof(string), typeof(wxdActivity));




[Browsable(true)]


[DesignerSerializationVisibility




(DesignerSerializationVisibility.Visible)]


public string wxdValue






{


get






{


return ((string)(base.GetValue(wxdActivity.wxdValueProperty)));


}


set






{


base.SetValue(wxdActivity.wxdValueProperty, value);


}


}




}






//自定义设计器


public class wxdActivityDesigner : ActivityDesigner






{




protected override




System.Collections.ObjectModel.ReadOnlyCollection<DesignerAction> DesignerActions






{


get






{


List<DesignerAction> list = new List<DesignerAction>();


foreach (DesignerAction temp in base.DesignerActions)






{


list.Add(new DesignerAction(this, temp.ActionId, temp.Text));


}


return list.AsReadOnly();


}


}




protected override ActivityDesignerVerbCollection Verbs






{


get






{


ActivityDesignerVerbCollection NewVerbs = new




ActivityDesignerVerbCollection();


NewVerbs.AddRange(base.Verbs);




ActivityDesignerVerb menu = new ActivityDesignerVerb(this,




DesignerVerbGroup.View, "设置wxdValue", new EventHandler(menu_click));


NewVerbs.Add(menu);




return NewVerbs;


}


}




//当添加的菜单单击时要执行的操作


private void menu_click(object sender, EventArgs e)






{




using (wxdSetForm wf = new wxdSetForm())






{


string v = (string)this.Activity.GetValue




(wxdActivity.wxdValueProperty);




wf.Value = v;


wf.ShowDialog();


this.Activity.SetValue(wxdActivity.wxdValueProperty,wf.Value);


}






}


}




//自定义数据设置窗体


public class wxdSetForm : System.Windows.Forms.Form






{


public string Value;


System.Windows.Forms.TextBox tx = new System.Windows.Forms.TextBox();


System.Windows.Forms.Button bt = new System.Windows.Forms.Button();


public wxdSetForm()






{


bt.Top=30;


this.Controls.Add(tx);


this.Controls.Add(bt);


bt.Click += new EventHandler(bt_Click);


bt.Text = "确定";


this.Load += new EventHandler(wxdSetForm_Load);


}




void wxdSetForm_Load(object sender, EventArgs e)






{


this.tx.Text = Value;


}




void bt_Click(object sender, EventArgs e)






{


this.Value = this.tx.Text;


this.Hide();


}


}


}
以上生成的Activity可以在VS中使用，也可以在我以前的流程设计器例子中使用





4.为Activity添加属性验证器


using System.Workflow.ComponentModel;


using System.ComponentModel;


using System.Workflow.ComponentModel.Design;


using System.Drawing;


using System.Drawing.Drawing2D;


using System.ComponentModel.Design;


using System;


using System.Collections.Generic;


using System.Workflow.ComponentModel.Compiler;


namespace wxwinter






{




//自定义Activity


[ActivityValidator(typeof(wxdActivityValidator))]


public class wxdActivity : System.Workflow.ComponentModel.Activity






{


public static DependencyProperty wxdValueProperty =




DependencyProperty.Register("wxdValue", typeof(string), typeof(wxdActivity));




[Browsable(true)]


[DesignerSerializationVisibility




(DesignerSerializationVisibility.Visible)]


public string wxdValue






{


get






{


return ((string)(base.GetValue(wxdActivity.wxdValueProperty)));


}


set






{


base.SetValue(wxdActivity.wxdValueProperty, value);


}


}




}


//验证器类


public class wxdActivityValidator :




System.Workflow.ComponentModel.Compiler.ActivityValidator






{


public override ValidationErrorCollection ValidateProperties




(ValidationManager manager, object obj)






{


ValidationErrorCollection Errors = base.ValidateProperties(manager,




obj);




if (obj != null)






{


this.wxdValueValidator(Errors, (wxdActivity)obj);


}


return Errors;


}




private void wxdValueValidator(ValidationErrorCollection Errors,




wxdActivity obj)






{


if (obj.wxdValue=="")






{


Errors.Add(ValidationError.GetNotSetValidationError




(wxdActivity.wxdValueProperty.Name));


}




}




}




}



5.运行时动态将字符串编译为C#可执行代码
(与WF无关，这是C#的基础知识，在作流程设计器时有时会用到)


private void button1_Click(object sender, EventArgs e)






{


CSharpCodeProvider CSharp = new CSharpCodeProvider();






String[] dll =

{ "System.dll", "System.Windows.Forms.dll" };




CompilerParameters 编译参数 = new CompilerParameters(dll);




编译参数.GenerateExecutable = false;




编译参数.GenerateInMemory = true;




string 代码串 = this.textBox1.Text;




CompilerResults 结果 = CSharp.CompileAssemblyFromSource(编译参数, 代




码串);




Assembly 程序集 = 结果.CompiledAssembly;




object 动态对象 = 程序集.CreateInstance("wxd");




MethodInfo 方法 = 动态对象.GetType().GetMethod("setText");






object[] 参数 =

{ this.button1 };




object s = 方法.Invoke(动态对象, 参数);




System.Console.WriteLine(s);




}

文本框中的文本代码

class wxd
{
public string setText(System.Windows.Forms.Control ct)
{
ct.Text = "按钮提示文字被我修改了";

System.Windows.Forms.MessageBox.Show("wxwinter");

return "ok";
}
}



例子:http://www.cnblogs.com/Files/foundation/WindowsApplication1.rar