Я нашел эту вспомогательную функцию в CodeProject, которая призвана предоставить реализацию функции SQL LIKE. Это работает довольно хорошо, но есть тестовый пример, в котором он не работает из-за слишком быстрого сопоставления подстановочного знака %.
Функция:
public static bool Like(this string s, string match, bool CaseInsensitive = true)
{
//Nothing matches a null mask or null input string
if (match == null || s == null)
return false;
//Null strings are treated as empty and get checked against the mask.
//If checking is case-insensitive we convert to uppercase to facilitate this.
if (CaseInsensitive)
{
s = s.ToUpperInvariant();
match = match.ToUpperInvariant();
}
//Keeps track of our position in the primary string - s.
int j = 0;
//Used to keep track of multi-character wildcards.
bool matchanymulti = false;
//Used to keep track of multiple possibility character masks.
string multicharmask = null;
bool inversemulticharmask = false;
for (int i = 0; i < match.Length; i++)
{
//If this is the last character of the mask and its a % or * we are done
if (i == match.Length - 1 && (match[i] == '%' || match[i] == '*'))
return true;
//A direct character match allows us to proceed.
var charcheck = true;
//Backslash acts as an escape character. If we encounter it, proceed
//to the next character.
if (match[i] == '\\')
{
i++;
if (i == match.Length)
i--;
}
else
{
//If this is a wildcard mask we flag it and proceed with the next character
//in the mask.
if (match[i] == '%' || match[i] == '*')
{
matchanymulti = true;
continue;
}
//If this is a single character wildcard advance one character.
if (match[i] == '_')
{
//If there is no character to advance we did not find a match.
if (j == s.Length)
return false;
j++;
continue;
}
if (match[i] == '[')
{
var endbracketidx = match.IndexOf(']', i);
//Get the characters to check for.
multicharmask = match.Substring(i + 1, endbracketidx - i - 1);
//Check for inversed masks
inversemulticharmask = multicharmask.StartsWith("^");
//Remove the inversed mask character
if (inversemulticharmask)
multicharmask = multicharmask.Remove(0, 1);
//Unescape \^ to ^
multicharmask = multicharmask.Replace("\\^", "^");
//Prevent direct character checking of the next mask character
//and advance to the next mask character.
charcheck = false;
i = endbracketidx;
//Detect and expand character ranges
if (multicharmask.Length == 3 && multicharmask[1] == '-')
{
var newmask = "";
var first = multicharmask[0];
var last = multicharmask[2];
if (last < first)
{
first = last;
last = multicharmask[0];
}
var c = first;
while (c
Подробнее здесь: [url]https://stackoverflow.com/questions/79375717/like-implementation-is-too-eager[/url]
Я нашел эту вспомогательную функцию в CodeProject, которая призвана предоставить реализацию функции SQL LIKE. Это работает довольно хорошо, но есть тестовый пример, в котором он не работает из-за слишком быстрого сопоставления подстановочного знака %. Функция: [code]public static bool Like(this string s, string match, bool CaseInsensitive = true) { //Nothing matches a null mask or null input string if (match == null || s == null) return false; //Null strings are treated as empty and get checked against the mask. //If checking is case-insensitive we convert to uppercase to facilitate this. if (CaseInsensitive) { s = s.ToUpperInvariant(); match = match.ToUpperInvariant(); } //Keeps track of our position in the primary string - s. int j = 0; //Used to keep track of multi-character wildcards. bool matchanymulti = false; //Used to keep track of multiple possibility character masks. string multicharmask = null; bool inversemulticharmask = false; for (int i = 0; i < match.Length; i++) { //If this is the last character of the mask and its a % or * we are done if (i == match.Length - 1 && (match[i] == '%' || match[i] == '*')) return true; //A direct character match allows us to proceed. var charcheck = true; //Backslash acts as an escape character. If we encounter it, proceed //to the next character. if (match[i] == '\\') { i++; if (i == match.Length) i--; } else { //If this is a wildcard mask we flag it and proceed with the next character //in the mask. if (match[i] == '%' || match[i] == '*') { matchanymulti = true; continue; } //If this is a single character wildcard advance one character. if (match[i] == '_') { //If there is no character to advance we did not find a match. if (j == s.Length) return false; j++; continue; } if (match[i] == '[') { var endbracketidx = match.IndexOf(']', i); //Get the characters to check for. multicharmask = match.Substring(i + 1, endbracketidx - i - 1); //Check for inversed masks inversemulticharmask = multicharmask.StartsWith("^"); //Remove the inversed mask character if (inversemulticharmask) multicharmask = multicharmask.Remove(0, 1); //Unescape \^ to ^ multicharmask = multicharmask.Replace("\\^", "^");
//Prevent direct character checking of the next mask character //and advance to the next mask character. charcheck = false; i = endbracketidx; //Detect and expand character ranges if (multicharmask.Length == 3 && multicharmask[1] == '-') { var newmask = ""; var first = multicharmask[0]; var last = multicharmask[2]; if (last < first) { first = last; last = multicharmask[0]; } var c = first; while (c
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