String.IndexOf Method (Char, Int32, Int32)

 
System_CAPS_noteNote

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Reports the zero-based index of the first occurrence of the specified character in this instance. The search starts at a specified character position and examines a specified number of character positions.

Namespace:   System
Assembly:  mscorlib (in mscorlib.dll)

member IndexOf : 
        value:char *
        startIndex:int *
        count:int -> int

Parameters

value
Type: System.Char

A Unicode character to seek.

startIndex
Type: System.Int32

The search starting position.

count
Type: System.Int32

The number of character positions to examine.

Return Value

Type: System.Int32

The zero-based index position of value from the start of the string if that character is found, or -1 if it is not.

Exception Condition
ArgumentOutOfRangeException

count or startIndex is negative.

-or-

startIndex is greater than the length of this string.

-or-

count is greater than the length of this string minus startIndex.

The search begins at startIndex and continues to startIndex + count -1. The character at startIndex + count is not included in the search.

Index numbering starts from 0 (zero). The startIndex parameter can range from 0 to the length of the string instance.

This method performs an ordinal (culture-insensitive) search, where a character is considered equivalent to another character only if their Unicode scalar values are the same. To perform a culture-sensitive search, use the CompareInfo.IndexOf method, where a Unicode scalar value representing a precomposed character, such as the ligature "Æ" (U+00C6), might be considered equivalent to any occurrence of the character's components in the correct sequence, such as "AE" (U+0041, U+0045), depending on the culture.

The following example demonstrates the IndexOf method.

No code example is currently available or this language may not be supported.

Universal Windows Platform
Available since 8
.NET Framework
Available since 1.1
Portable Class Library
Supported in: portable .NET platforms
Silverlight
Available since 2.0
Windows Phone Silverlight
Available since 7.0
Windows Phone
Available since 8.1
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