How Can Dynamic LINQ Select Specific Columns On-Demand?

Dynamic linq: Dynamic selection of a specific column

When dealing with a class like the

Data

class provided in the problem, it is necessary to choose a specific column during the linq operation. This task can be completed by dynamically created Lambda expressions passed to SELECT method. For this reason, the

Createnewstatement

Method. It receives a string containing the required field name as input and dynamically constructs Lambda expressions that execute the necessary column. In this method: Create an expression parameter, indicating the input object passed to Lambda.

Use Expression.new
• Method to create a new example of
Data
• class. Use Expression.split Method to divide the input string into a list of single field names.
For each field name, use
• Type.getproperty Get the corresponding attributes in the Data
class.
• Use Expression.property The original value of the retrieval attribute. Use Expression.bind
Create a binding expression to set the attribute value in the new instance.
• Use Expression.memberinit Binded expression into a single initialization expression.
• Finally, use EXPRESSION.LAMBDA Create lambda expression and compile it into appropriate types of commission.
• With the Createnewstatement method, you can call it by using the required field name as a parameter to dynamically select a specific column. For example, select Field1
and
• Field2 column: column:

This method provides a common method that dynamically selects columns in the Linq operation. Even if the selected field is not known during compilation.

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