GetItemRequest Class | AWS SDK for .NET V2

Container for the parameters to the GetItem operation. The GetItem operation returns a set of attributes for the item with the given primary key. If there is no matching item, GetItem does not return any data.

GetItem provides an eventually consistent read by default. If your application requires a strongly consistent read, set ConsistentRead to true. Although a strongly consistent read might take more time than an eventually consistent read, it always returns the last updated value.

Inheritance Hierarchy

System.Object
  Amazon.Runtime.AmazonWebServiceRequest
    Amazon.DynamoDBv2.AmazonDynamoDBRequest
      Amazon.DynamoDBv2.Model.GetItemRequest

Namespace: Amazon.DynamoDBv2.Model
Assembly: AWSSDK.dll
Version: (assembly version)

Syntax

public class GetItemRequest : AmazonDynamoDBRequest
         IRequestEvents

The GetItemRequest type exposes the following members

Constructors

	Name	Description
	GetItemRequest()	Empty constructor used to set properties independently even when a simple constructor is available
	GetItemRequest(string, Dictionary<String, AttributeValue>)
	GetItemRequest(string, Dictionary<String, AttributeValue>, bool)

Properties

Name	Type	Description
AttributesToGet	System.Collections.Generic.List<System.String>	Gets and sets the property AttributesToGet. This is a legacy parameter, for backward compatibility. New applications should use ProjectionExpression instead. Do not combine legacy parameters and expression parameters in a single API call; otherwise, DynamoDB will return a ValidationException exception. This parameter allows you to retrieve attributes of type List or Map; however, it cannot retrieve individual elements within a List or a Map. The names of one or more attributes to retrieve. If no attribute names are provided, then all attributes will be returned. If any of the requested attributes are not found, they will not appear in the result. Note that AttributesToGet has no effect on provisioned throughput consumption. DynamoDB determines capacity units consumed based on item size, not on the amount of data that is returned to an application.
ConsistentRead	System.Boolean	Gets and sets the property ConsistentRead. Determines the read consistency model: If set to `true`, then the operation uses strongly consistent reads; otherwise, the operation uses eventually consistent reads.
ExpressionAttributeNames	System.Collections.Generic.Dictionary<System.String, System.String>	Gets and sets the property ExpressionAttributeNames. One or more substitution tokens for attribute names in an expression. The following are some use cases for using ExpressionAttributeNames: To access an attribute whose name conflicts with a DynamoDB reserved word. To create a placeholder for repeating occurrences of an attribute name in an expression. To prevent special characters in an attribute name from being misinterpreted in an expression. Use the # character in an expression to dereference an attribute name. For example, consider the following attribute name: `Percentile` The name of this attribute conflicts with a reserved word, so it cannot be used directly in an expression. (For the complete list of reserved words, see Reserved Words in the Amazon DynamoDB Developer Guide). To work around this, you could specify the following for ExpressionAttributeNames: `{"#P":"Percentile"}` You could then use this substitution in an expression, as in this example: `#P = :val` Tokens that begin with the : character are expression attribute values, which are placeholders for the actual value at runtime. For more information on expression attribute names, see Accessing Item Attributes in the Amazon DynamoDB Developer Guide.
Key	System.Collections.Generic.Dictionary<System.String, Amazon.DynamoDBv2.Model.AttributeValue>	Gets and sets the property Key. A map of attribute names to AttributeValue objects, representing the primary key of the item to retrieve. For the primary key, you must provide all of the attributes. For example, with a simple primary key, you only need to provide a value for the partition key. For a composite primary key, you must provide values for both the partition key and the sort key.
ProjectionExpression	System.String	Gets and sets the property ProjectionExpression. A string that identifies one or more attributes to retrieve from the table. These attributes can include scalars, sets, or elements of a JSON document. The attributes in the expression must be separated by commas. If no attribute names are specified, then all attributes will be returned. If any of the requested attributes are not found, they will not appear in the result. For more information, see Accessing Item Attributes in the Amazon DynamoDB Developer Guide. ProjectionExpression replaces the legacy AttributesToGet parameter.
ReturnConsumedCapacity	Amazon.DynamoDBv2.ReturnConsumedCapacity	Gets and sets the property ReturnConsumedCapacity.
TableName	System.String	Gets and sets the property TableName. The name of the table containing the requested item.

Examples

This example shows how to get an item in a table.

GetItem sample


// Create a client
AmazonDynamoDBClient client = new AmazonDynamoDBClient();

// Define item key
//  Hash-key of the target item is string value "Mark Twain"
//  Range-key of the target item is string value "The Adventures of Tom Sawyer"
Dictionary<string, AttributeValue> key = new Dictionary<string, AttributeValue>
{
    { "Author", new AttributeValue { S = "Mark Twain" } },
    { "Title", new AttributeValue { S = "The Adventures of Tom Sawyer" } }
};

// Create GetItem request
GetItemRequest request = new GetItemRequest
{
    TableName = "SampleTable",
    Key = key,
};

// Issue request
var result = client.GetItem(request);

// View response
Console.WriteLine("Item:");
Dictionary<string, AttributeValue> item = result.Item;
foreach (var keyValuePair in item)
{
    Console.WriteLine("{0} : S={1}, N={2}, SS=[{3}], NS=[{4}]",
        keyValuePair.Key,
        keyValuePair.Value.S,
        keyValuePair.Value.N,
        string.Join(", ", keyValuePair.Value.SS ?? new List<string>()),
        string.Join(", ", keyValuePair.Value.NS ?? new List<string>()));
}

Version Information

.NET Framework:
Supported in: 4.5, 4.0, 3.5

.NET for Windows Store apps:
Supported in: Windows 8.1, Windows 8

.NET for Windows Phone:
Supported in: Windows Phone 8.1, Windows Phone 8