In. Net execute js

 

use Noesis.Javascript open source components can be done in. net js script execution , while js script can also call C # function . This component is obtained by: in NuGet enter a search "Noesis" to find.

 

us to be a search function : Users can enter in textbox to filter the list js script recording , the interface is as follows :

 

 

Then , click filter button after UI:

 

 

look, screened out, the following code (js can call C # to write UserInfo class each attribute )

 

  

public class UserInfo 
    { 
        public string FirstName { get; set; } 
        public string LastName { get; set; } 
        public int Age { get; set; } 
        public override string ToString() 
        { 
            return string.Format("{0}, {1}: {2}", FirstName, LastName, Age); 
        } 
    } 
 
private void btnSearch_Click(object sender, EventArgs e) 
        { 
            List<UserInfo> users = FilterUsers(txtFilter.Text.Trim()); 
            lstUsers.DataSource = users; 
        } 
 
        private List<UserInfo> FilterUsers(string jsFilter) 
        { 
            List<UserInfo> results = new List<UserInfo>(); 
            if (jsFilter.Trim().Length == 0) 
                return this.users; 
 
            try 
            { 
                using (JavascriptContext context = new JavascriptContext()) 
                { 
                    foreach (UserInfo user in this.users) 
                    { 
                        context.SetParameter("user", user); 
                        context.SetParameter("isInclude", false); 
                        string js = string.Format(@" 
                                                if({0}) 
                                                    isInclude=true; 
                                                else 
                                                    isInclude=false;", jsFilter); 
                        context.Run(js); 
                        bool isInclude = (bool)context.GetParameter("isInclude"); 
                        if (isInclude) 
                            results.Add(user); 
                    } 
                } 
            } 
            catch 
            { 
                txtFilter.Focus(); 
                txtFilter.SelectAll(); 
                return this.users; 
            } 
 
            return results; 
        }

 

 

 

we look Efficiency :

 

  

private void btnTest_Click(object sender, EventArgs e) 
        { 
            using (JavascriptContext context = new JavascriptContext()) 
            { 
                Stopwatch sw = new Stopwatch(); 
                sw.Start(); 
                int i=1000000; 
                while(i-- > 0) 
                { 
                    context.SetParameter("ii", 1); 
                    context.SetParameter("jj", 2); 
                    context.SetParameter("sum", 0); 
                    string js = string.Format(@"sum=ii+jj;"); 
                    context.Run(js); 
                    int sum = (int)context.GetParameter("sum"); 
                } 
                sw.Stop(); 
 
                long useJS_Total = sw.ElapsedMilliseconds; 
                float useJS_Average = ((float)sw.ElapsedMilliseconds) / 1000000; 
 
                sw.Reset(); 
                sw.Start(); 
                i = 1000000; 
                while (i-- > 0) 
                { 
                    int ii = 1; 
                    int jj = 2; 
                    int sum = 0; 
                    sum = ii + jj; 
                } 
                sw.Stop(); 
 
                long nouseJS_Total = sw.ElapsedMilliseconds; 
                float nouseJS_Average = ((float)sw.ElapsedMilliseconds) / 1000000; 
 
                string msg = ""; 
                msg += string.Format("useJS_Total: {0}\r\n", useJS_Total); 
                msg += string.Format("useJS_Average: {0}\r\n\r\n\r\n", useJS_Average); 
                msg += string.Format("nouseJS_Total: {0}\r\n", nouseJS_Total); 
                msg += string.Format("nouseJS_Average: {0}\r\n\r\n\r\n", nouseJS_Average); 
 
                MessageBox.Show(msg); 
            } 
        }

 

 

 

results ( js engine above is calculated time , the following is a pure C # computing time , tragedy ah ):

 

 

Conclusion :

 

  
1. this Noesis.Javascript only for performance-demanding applications
  
2. performance depends Lua