public static int EvalInt(string statment)
{
var result = ExpressionEvaluator.Eval(statment);
return(Convert.ToInt32(result));
}
/// <summary>
/// 执行并返回一个 bool 值
/// </summary>
/// <param name="statment"></param>
/// <returns></returns>
public static bool EvalBoolean(string statment)
{
var result = ExpressionEvaluator.Eval(statment);
return(Convert.ToBoolean(result));
}
public static decimal EvalDecimal(string statment)
{
var result = ExpressionEvaluator.Eval(statment);
return(Convert.ToDecimal(result));
}
public string Compile(string expr, IDictionary <string, object> input)
{
if (string.IsNullOrWhiteSpace(expr))
{
return(string.Empty);
}
else if (input == null || input.Any() == false)
{
return(expr);
}
#if ENABLE_CACHE
var cacheKeyName = GetCacheKey(expr, input);
if (EnableCache && CacheAlive > 0)
{
// 判断内存缓存
if (_expressionCache.Contains(cacheKeyName))
{
return(_expressionCache.Get(cacheKeyName) as string);
}
}
#endif
var tempBuilder = new StringBuilder(expr);
foreach (var item in input)
{
tempBuilder.Replace(item.Key, item.Value.ToString()); // 替换表达式的值
}
/*
* var matches = _paramReg.Matches(tempBuilder.ToString());
* foreach (Match item in matches)
* {
* var statment = item.Value.Replace("$", "");
* // 括号补偿
* int leftbracket = statment.Count(c => c == '(');
* int rightbracket = statment.Count(c => c == ')');
* while (leftbracket > rightbracket)
* {
* statment = string.Concat(statment, ')');
* leftbracket -= 1;
* }
* var result = ExpressionEvaluator.Eval(statment);
* tempBuilder.Replace(statment, result.ToString());// 替换到输出文本
* }
*/
// JS 表达式(代码)截取、替换，这里性能不够好，得优化
var tempStr = tempBuilder.ToString();
int startIndex = tempStr.IndexOf(MarkChar);
int nextIndex = tempStr.IndexOf(MarkChar, startIndex + 1);
while (nextIndex > -1)
{
var statment = tempStr.Substring(startIndex + 1, nextIndex - startIndex - 1);
var result = ExpressionEvaluator.Eval(statment);
tempBuilder.Replace(statment, result.ToString());// 替换到输出文本
nextIndex = tempStr.IndexOf(MarkChar, nextIndex + 1);
if (nextIndex > -1)
{
startIndex = nextIndex;
nextIndex = tempStr.IndexOf(MarkChar, startIndex + 1);
}
}
#if ENABLE_CACHE
if (EnableCache && CacheAlive > 0)
{
_expressionCache.AddOrGetExisting(cacheKeyName, tempBuilder.ToString(), DateTime.Now.AddSeconds(CacheAlive));
}
#endif
// 清理标记字符
tempBuilder.Replace(MarkChar.ToString(), string.Empty);
return(tempBuilder.ToString());
}