string-handling.md

String Handling

Many .Net string operations are supported by N1QL, and can be used directly in your LINQ queries.

##Supported String Operations

• Length property
• Character index (i.e. str[2])
• ToUpper() and ToLower()
• String concatenation, using String.Concat(...) or the + operator
• Trim(), Trim(char[]), TrimStart(), and TrimEnd()
• Substring(startIndex) and Substring(startIndex, length)
• IndexOf(char) and IndexOf(string)
• Split() and Split(char)
• Replace(oldValue, newValue)

##String Comparisons String equality comparisons can be performed using the == and != operators.

using (var cluster = new Cluster()) {
	using (var bucket = cluster.OpenBucket("beer-sample")) {
		var context = new BucketContext(bucket);

		var query = from beer in context.Query<Beer>()
					where beer.Name == "21A IPA"
					select beer;

		foreach (var doc in query) {
			// do work
			// query will return beers with the name 21A IPA
		}
	}
}

For other string comparison types, you may use String.Compare. The most readable method is to compare the two strings, then always compare the result to zero.

using (var cluster = new Cluster()) {
	using (var bucket = cluster.OpenBucket("beer-sample")) {
		var context = new BucketContext(bucket);

		var query = from beer in context.Query<Beer>()
					where String.Compare(beer.Name, "21A IPA") > 0
					select beer;

		foreach (var doc in query) {
			// do work
			// query will return beers with a name greater than, but not equal to, 21A IPA
		}
	}
}

If you use this format, then the comparison operator before the zero is always the same as the comparison you're using for the strings.

Note: Any call to String.Compare within a query must be combined with a comparison to either -1, 0, or 1. Any other usage will throw an exception.