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EdmFunctions.Substring(DbExpression, DbExpression, DbExpression) Method

Definition

Creates a DbFunctionExpression that invokes the canonical 'Substring' function with the specified arguments, which must have a string and integer numeric result types. The result type of the expression is string.

public:
[System::Runtime::CompilerServices::Extension]
 static System::Data::Common::CommandTrees::DbFunctionExpression ^ Substring(System::Data::Common::CommandTrees::DbExpression ^ stringArgument, System::Data::Common::CommandTrees::DbExpression ^ start, System::Data::Common::CommandTrees::DbExpression ^ length);
public static System.Data.Common.CommandTrees.DbFunctionExpression Substring (this System.Data.Common.CommandTrees.DbExpression stringArgument, System.Data.Common.CommandTrees.DbExpression start, System.Data.Common.CommandTrees.DbExpression length);
static member Substring : System.Data.Common.CommandTrees.DbExpression * System.Data.Common.CommandTrees.DbExpression * System.Data.Common.CommandTrees.DbExpression -> System.Data.Common.CommandTrees.DbFunctionExpression
<Extension()>
Public Function Substring (stringArgument As DbExpression, start As DbExpression, length As DbExpression) As DbFunctionExpression

Parameters

stringArgument
DbExpression

An expression that specifies the string from which to extract the substring.

start
DbExpression

An expression that specifies the starting index from which the substring should be taken.

length
DbExpression

An expression that specifies the length of the substring.

Returns

A new DbFunctionExpression that returns the substring of length length from stringArgument starting at start.

Exceptions

stringArgument, start, or length is null.

stringArgument, start, or length is invalid.

Remarks

Substring requires that the index specified by start be <b>1-based</b>.

Applies to