Question

使用带有正则表达式的test（）的第二次调用函数由于某种原因返回不同的结果。我看不出造成这种差异的原因。我想也许它与对象引用有关，但无法跟踪它。

如果我改变函数使用match（）（参见第二个函数matchTrees（））。它可以找到对函数的第一次和第二次调用。下面有控制台输出的代码段。

var trees = [
    {"regX" : /alder$/gi,"id":"Alder"},
    {"regX" : /elm/gi,"id":"Elm"},
    {"regX" : /ash/gi,"id":"Ash"}
    ];

function testTrees(treeArray){
    var matchedTrees = [];
    var i, j;
    for (i = 0; i < treeArray.length; i++) { 
        for (j = 0; j < trees.length; j++) {
             if(trees[j].regX.test(treeArray[i])){
             //if(treeArray[i].match(trees[j].regX)){
                matchedTrees.push(trees[j]);

                break;    
            }    
        }        
    }
    return matchedTrees;
}

function matchTrees(treeArray){
    var matchedTrees = [];
    var i, j;
    for (i = 0; i < treeArray.length; i++) { 
        for (j = 0; j < trees.length; j++) {
             //if(trees[j].regX.test(treeArray[i])){
             if(treeArray[i].match(trees[j].regX)){
                matchedTrees.push(trees[j]);

                break;    
            }    
        }        
    }
    return matchedTrees;
}

var treeArray = ["Elm", "Ash"];
var firstresult;
var secondresult;

console.log("run twice with test()");
firstresult = testTrees(treeArray);
console.log(JSON.stringify(firstresult));

secondresult = testTrees(treeArray);
console.log(JSON.stringify(secondresult));

console.log("run twice with match()");
firstresult = matchTrees(treeArray);
console.log(JSON.stringify(firstresult));

secondresult = matchTrees(treeArray);
console.log(JSON.stringify(secondresult));

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regex test（）vs Match（） - 使用test（）在第二次运行时出现错误结果

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