String::IndexOf Method (String, Int32, Int32, StringComparison)
Reports the zero-based index of the first occurrence of the specified string in the current String object. Parameters specify the starting search position in the current string, the number of characters in the current string to search, and the type of search to use for the specified string.
Assembly: mscorlib (in mscorlib.dll)
public: int IndexOf( String^ value, int startIndex, int count, StringComparison comparisonType )
Parameters
- value
- Type: System::String
The string to seek.
- startIndex
- Type: System::Int32
The search starting position.
- count
- Type: System::Int32
The number of character positions to examine.
- comparisonType
- Type: System::StringComparison
One of the enumeration values that specifies the rules for the search.
Return Value
Type: System::Int32The zero-based index position of the value parameter if that string is found, or -1 if it is not. If value is Empty, the return value is startIndex.
| Exception | Condition |
|---|---|
| ArgumentNullException | value is nullptr. |
| ArgumentOutOfRangeException | count or startIndex is negative. -or- startIndex is greater than the length of this instance. -or- count is greater than the length of this instance minus startIndex. |
| ArgumentException | comparisonType is not a valid System::StringComparison value. |
Index numbering starts from zero. This means that startIndex parameter can range from 0 to the length of the string instance.
The search begins at startIndex and continues to startIndex + count -1. The character at startIndex + count is not included in the search.
The comparisonType parameter specifies to search for the value parameter using the current or invariant culture, using a case-sensitive or case-insensitive search, and using word or ordinal comparison rules.
The following example demonstrates three overloads of the IndexOf method that find the first occurrence of a string within another string using different values of the StringComparison enumeration.
Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.