This post assumes you’ve read my previous Converting SQL to LINQ posts.
I haven’t had much in the way of specific requests for more LINQ posts, so I’d still welcome any suggestions that people want to offer. I did get one request about how to mimic the LIKE keyword functionality in VB LINQ.
In SQL, the LIKE keyword compares a string field against a pattern and returns a Boolean value representing whether the string matches the pattern. For example, if I wanted to select every customer in the 206 area code, I could use this SQL query:
WHERE Phone LIKE ‘206*’
The LIKE expression can include certain wildcard characters, which may differ from system to system. In the above example, * matches any string, so ‘206*’ represents any string that begins with 206.
VB happens to include a Like operator, so this is an easy conversion to make. The LINQ version of this above SQL expression is specified below:
From Contact In CustomerTable _
Where Contact.Phone Like “206*”
The VB Like keyword has the following wildcards:
? Matches any single character
* Matches zero or more characters
# Matches any single digit
[ charlist ] Matches any single character in the charlist
[! charlist ] Matches any single character not in the charlist
More extensive documentation of the Like operator can be found here.
- Bill Horst, VB IDE Test