DataBinding异常求助：System.Data.DataRowView不含'Tasklist'属性

Hey, let's work through this GridView binding issue you're facing. That error message tells us exactly what's going wrong: the second GridView (the one showing steps when you click a task) is trying to reference a field called Tasklist, but the data source you're feeding it (a DataRowView from your steps data) doesn't have that field at all. Here's how to track down and fix the problem:

1. First, find where Tasklist is being referenced #

The code you shared only includes the task list GridView (tasklistsGridView), so the issue is definitely in your steps GridView configuration. Check these places:

• Look at the BoundField or TemplateField definitions in your steps GridView. Do any of them use Bind("Tasklist") or Eval("Tasklist")?
• If you're using a SqlDataSource to bind the steps GridView, check its SelectCommand—does the SQL query return a column named Tasklist?

2. Common Causes & Fixes #

Cause 1: Typos in the field name #

ASP.NET is case-sensitive when it comes to field names! If your database column is actually TaskList (capital L) but you wrote Tasklist (lowercase l) in your binding expression, that's enough to trigger this error.

• Fix: Double-check the spelling and capitalization of the field name in your GridView markup against the actual column names in your steps data source. Make them match exactly.

Cause 2: Your data source doesn't include the Tasklist field #

When you select a task and load the steps data (probably in the tasklistsGridView_SelectedIndexChanged event), the query you're using to get steps data isn't returning a Tasklist column. Maybe you forgot to include it in your SQL select statement, or you're querying a table that doesn't have this field at all.

• Fix:
  1. Open your code-behind and find the method that loads steps data for the selected task.
  2. Check the SQL query—does it explicitly select the Tasklist column? If not, add it (or replace it with the correct column name you actually need).
  3. For debugging, you can print out the column names of your data source to confirm what's actually being returned:

     // Add this right before binding your steps GridView
     DataTable stepsData = GetStepsForSelectedTask(selectedTaskId); // Replace with your actual method
     foreach (DataColumn col in stepsData.Columns)
     {
         System.Diagnostics.Debug.WriteLine($"Column Name: {col.ColumnName}");
     }
     stepsGridView.DataSource = stepsData;
     stepsGridView.DataBind();
     

     Run your app and check the Output window in Visual Studio—you'll see exactly which columns are in your data source.

Cause 3: You confused a table name with a field name #

It sounds like you're linking tasks and steps—maybe you meant to reference a task ID field (like TaskId) to associate steps with their parent task, but accidentally wrote Tasklist (the name of your task table) instead? If your steps table has a TaskId column that maps to the task table's Id, that's the field you should be using in your query or binding, not Tasklist.

• Fix: Replace any references to Tasklist with the correct foreign key field name (like TaskId) in your GridView markup or SQL query.

3. Quick Additional Checks #

• If you're using a SqlDataSource for the steps GridView, verify that its SelectCommand is filtering steps by the selected task's ID correctly, and that all columns in the command exist in your steps table.
• Make sure the data you're binding to the steps GridView is actually related to the selected task—sometimes a bug in the filtering logic can return an empty or incorrect dataset that's missing expected fields.

Start with these steps, and you should be able to resolve the binding error quickly!

内容的提问来源于stack exchange，提问作者Shubham Mehta