Need to get the selected row in a grid

Question

I am trying to code a page with a grid with 2 columns:

File Name

File Type (in a dropdown control)

I have up to 10 file names in a Data Class, and I am having a few errors before I can start debugging this page.

I am attaching the class with the file name, there is also a file count updated from a previous page (as well as the file names)

The way I built the data class is causing me problems.

Fields.cs (could not attach .cs file type)

using System;

using System.Collections.Generic;

using System.Linq;

using System.Threading.Tasks;

using System.ComponentModel.DataAnnotations;

using System.Net.Http;

using System.Net.Http.Headers;

namespace server_sample.Data

{

public class Files

{

public static string Name1 { get; set; }

public static string Path1 { get; set; }

public static string Type1 { get; set; }

public static string Name2 { get; set; }

public static string Path2 { get; set; }

public static string Type2 { get; set; }

public static string Name3 { get; set; }

public static string Path3 { get; set; }

public static string Type3 { get; set; }

public static string Name4 { get; set; }

public static string Path4 { get; set; }

public static string Type4 { get; set; }

public static string Name5 { get; set; }

public static string Path5 { get; set; }

public static string Type5 { get; set; }

public static string Name6 { get; set; }

public static string Path6 { get; set; }

public static string Type6 { get; set; }

public static string Name7 { get; set; }

public static string Path7 { get; set; }

public static string Type7 { get; set; }

public static string Name8 { get; set; }

public static string Path8 { get; set; }

public static string Type8 { get; set; }

public static string Name9 { get; set; }

public static string Path9 { get; set; }

public static string Type9 { get; set; }

public static string Name10 { get; set; }

public static string Path10 { get; set; }

public static string Type10 { get; set; }

public static int Zfilecnt { get; set; }

}

And here is the component where I am trying to define each file type (with comments on the errors)

@page "/Define Files"

@using Syncfusion.Blazor.DropDowns

@using Syncfusion.Blazor.Grids

@using server_sample.Data

<SfGrid @ref="GridRef" AllowPaging="true" DataSource="@GridData" Toolbar="@(new List<string>() { "Delete", "Update" })">

</SfDropDownList>

</EditTemplate>

</GridColumn>

</SfDropDownList>

</EditTemplate>

</GridColumn>

</GridColumns>

</SfGrid>

@code

{

// <DropDownListEvents ValueChange="ValueChange"

// this is giving me an error that "can not convert from 'method group' to 'eventcallback'

//

SfGrid<Files> GridRef;

public List<Files> GridData { get; set; } = new List<Files>();

public List<string> FileTypes = new List<string>() { "Fixed ", "Comma Delim", "Tab Delim", "Excel", "SemiColon Delim", "DBF", "PDF", "Word", "XML", "Jason" };

string aux="";

public bool Enabled = false;

public class Files

{

public Files()

{

}

public Files(string FileName, string FileType)

{

/// Error DefineFiles.Files does not contain a definition for FileName or TypeID

/// I've coded the Fields class to accomodate up to 10 files how should I code it...

///

this.FileName = FileName;

this.TypeID = FileType;

}

public void ValueChange(@Syncfusion.Blazor.DropDowns.ChangeEventArgs<string, string> args)

{

// have to retrieve selected row to find which Data.Files.Type to update...

//Data.Files.

/* if (args.Value == "United States")

{

States = new List<string>() { "New York", "Virginia", "Washington" };

}

else if (args.Value == "Australia")

{

States = new List<string>() { "Queensland", "Tasmania", "Victoria" };

}*/

Enabled = true;

GridRef.PreventRender(false);

}

public string FileID { get; set; }

public string TypeID { get; set; }

protected override void OnInitialized()

{

for (int i = 1; i <= Data.Files.Zfilecnt; i++)

{

aux = "Name" + i.ToString();

GridData.Add(new Files(aux, FileTypes));

}

public class File

{

public string Name { get; set; }

public string Path { get; set; }

public string Type { get; set; }

}

public void OnActionBegin(ActionEventArgs<Files> args)

{

if (args.RequestType == Syncfusion.Blazor.Grids.Action.BeginEdit)

{

Enabled = false;

}

Renjith Singh Rajendran · Answer

Hi Paul, Greetings from Syncfusion support. We suggest you to refer and use as like the below highlighted codes to overcome the problems reported in code comments. //set based on TValue and TItem property public void ValueChange(@Syncfusion.Blazor.DropDowns.ChangeEventArgs args) { ... GridRef.PreventRender(false); } public class Files { public Files() { } public Files(string FileName, string FileType) { this.FileName = FileName; this.TypeID = FileType; } public string FileName { get; set; } public string TypeID { get; set; } } Please get back to us if you need further assistance. Regards, Renjith R

Paul · Answer

Thanks for your reply. I changed my code to:

@page "/Define Files"

@using Syncfusion.Blazor.DropDowns

@using Syncfusion.Blazor.Grids

@using server_sample.Data

<SfGrid @ref="GridRef" AllowPaging="true" DataSource="@GridData" Toolbar="@(new List<string>() { "Delete", "Update" })">

</SfDropDownList>

</EditTemplate>

</GridColumn>

</SfDropDownList>

</EditTemplate>

</GridColumn>

</GridColumns>

</SfGrid>

@code

{

SfGrid<Files> GridRef;

public List<Files> GridData { get; set; } = new List<Files>();

public List<string> FileTypes = new List<string>() { "Fixed ", "Comma Delim", "Tab Delim", "Excel", "SemiColon Delim", "DBF", "PDF", "Word", "XML", "Jason" };

string aux="";

public bool Enabled = false;

public class Files

{

public Files()

{

}

public Files(string FileName, string FileType)

{

this.FileName = FileName;

this.TypeID = FileType;

}

public string FileName { get; set; }

public string TypeID { get; set; }

}

public void ValueChange(@Syncfusion.Blazor.DropDowns.ChangeEventArgs<string, string> args)

{

// have to retrieve selected row to find which Data.Files.Type to update...

//Data.Files.

/* if (args.Value == "United States")

{

States = new List<string>() { "New York", "Virginia", "Washington" };

}

else if (args.Value == "Australia")

{

States = new List<string>() { "Queensland", "Tasmania", "Victoria" };

}*/

Enabled = true;

GridRef.PreventRender(false);

}

public string FileID { get; set; }

public string TypeID { get; set; }

protected override void OnInitialized()

{

for (int i = 1; i <= Data.Files.Zfilecnt; i++)

{

aux = "Name" + i.ToString();

// /////////////////////////////////////////////////////// New Error

// getting warning CS1503 Argument 2 - Can not convert from System.Collections.Generic.List<string> to 'string'

GridData.Add(new Files(aux, FileTypes));

}

public class File

{

public string Name { get; set; }

public string Path { get; set; }

public string Type { get; set; }

}

public void OnActionBegin(ActionEventArgs<Files> args)

{

if (args.RequestType == Syncfusion.Blazor.Grids.Action.BeginEdit)

{

Enabled = false;

}

I got the following compile errors

Severity Code Description Project File Line Suppression State

Error CS1662 Cannot convert lambda expression to intended delegate type because some of the return types in the block are not implicitly convertible to the delegate return type server-sample C:\Users\data\Downloads\Syncfusion\308\server-sample\Pages\Define Files.razor 1 Active

Error CS0246 The type or namespace name 'Orders' could not be found (are you missing a using directive or an assembly reference?) server-sample C:\Users\data\Downloads\Syncfusion\308\server-sample\Pages\Define Files.razor 1 Active

Error CS1662 Cannot convert lambda expression to intended delegate type because some of the return types in the block are not implicitly convertible to the delegate return type server-sample C:\Users\data\Downloads\Syncfusion\308\server-sample\Pages\Define Files.razor 1 Active

Error CS1503 Argument 1: cannot convert from 'System.Collections.Generic.List<string>' to 'System.Collections.Generic.IEnumerable<server_sample.Pages.Define_Files.File>' server-sample C:\Users\data\Downloads\Syncfusion\308\server-sample\Pages\Define Files.razor 13 Active

Error CS1503 Argument 2: cannot convert from 'method group' to 'EventCallback' server-sample C:\Users\data\Downloads\Syncfusion\308\server-sample\Pages\Define Files.razor 15 Active

Error CS0246 The type or namespace name 'Orders' could not be found (are you missing a using directive or an assembly reference?) server-sample C:\Users\data\Downloads\Syncfusion\308\server-sample\Pages\Define Files.razor 21 Active

Error CS0103 The name 'States' does not exist in the current context server-sample C:\Users\data\Downloads\Syncfusion\308\server-sample\Pages\Define Files.razor 21 Active

Error CS1503 Argument 2: cannot convert from 'System.Collections.Generic.List<string>' to 'string' server-sample C:\Users\data\Downloads\Syncfusion\308\server-sample\Pages\Define Files.razor 79 Active

Warning CS8032 An instance of analyzer System.Text.Json.SourceGeneration.JsonSourceGenerator cannot be created from C:\Users\data\.nuget\packages\system.text.json\6.0.0\analyzers\dotnet\roslyn3.11\cs\System.Text.Json.SourceGeneration.dll: Could not load file or assembly 'Microsoft.CodeAnalysis, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35' or one of its dependencies. The system cannot find the file specified.. server-sample 1 Active

Warning CS8032 An instance of analyzer System.Text.Json.SourceGeneration.JsonSourceGenerator cannot be created from C:\Users\data\.nuget\packages\system.text.json\6.0.0\analyzers\dotnet\roslyn4.0\cs\System.Text.Json.SourceGeneration.dll: Could not load file or assembly 'Microsoft.CodeAnalysis, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35' or one of its dependencies. The system cannot find the file specified.. server-sample 1 Active

Rahul Narayanasamy · Answer

Hi Paul, 

Thanks for the update. 

We are currently checking the reported problem at our end and we will update the further details within two business days. Until then we appreciate your patience. 

Regards, 
Rahul

Paul · Answer

Hello Raul and Syncfusion TeamI am also concerned with my design I created a class with room for 10 files (internal names, url names, and file types (along with a count variable) Which are filled out on a previous component UPLOAD.Once we get past the syntax error I intend to have a edit dropdown for a selected file/row and save the type on the same class (files.cs)Please let me know if this is good designPaul

Renjith Singh Rajendran · Answer

Hi Paul, 
 
We have prepared a runnable sample by modifying your shared codes. We suggest you to refer the comments mentioned in the below sample and check this from your side. 
Sample : https://www.syncfusion.com/downloads/support/directtrac/general/ze/ServerApp-1898572683 
 
And also we could see in your shared codes you are having two Files model class(on in a separate namespace under server_sample.Data and other in the same page in which you are having grid). We suggest you to ensure to remove these duplicated model class names. At this case, Grid will use the model class which you have provided in the page containing grid. 
 
We also suggest you to refer our documentation links and use valid codes in your application, 
https://blazor.syncfusion.com/documentation/datagrid/how-to/cascading-dropdownlist-with-grid-editing 
https://blazor.syncfusion.com/documentation/datagrid/editing 
https://blazor.syncfusion.com/documentation/dropdown-list/events 
https://blazor.syncfusion.com/documentation/dropdown-list/getting-started  
 
Kindly refer the above references and check this from your side. If you are still facing difficulties then kindly share with us a simple issue reproducing sample along with a video demo explaining your scenario and a detailed explanation of your complete requirement for us to proceed further. 
 
Regards, 
Renjith R