為什么str.replace()沒有效果

var obj1 = {
    "name": "",
    "children": [
        {
            "name": "第一句",
            "content": "1",
            "children": [
                {
                    "name": "第一句的子節(jié)點(diǎn)",
                    "content": "1children",
                    "children": [

                    ]
                }
            ]
        },
        {
            "name": "第二句",
            "content": "2",
            "children": [
                {
                    "name": "第二句的子節(jié)點(diǎn)",
                    "content": "2children",
                    "children": [
                        {
                            "name": "第二句的子節(jié)點(diǎn)的子節(jié)點(diǎn)",
                            "content": "2children2children",
                            "children": [

                            ]
                        }
                    ]
                }
            ]
        }
    ]
}

var obj2 = {
    "name":"第一句的子節(jié)點(diǎn)",
    "content":"1children",
    "children":[]
};

var patt = new RegExp(JSON.stringify(obj2),'g');

var newData = JSON.stringify(obj1).replace(patt,'1111111111111');
console.log(newData);

上面這段代碼為什么沒辦法從obj1中剪掉obj2這一段呢？
輸出的結(jié)果還是完完整整的obj1，仿佛什么都沒操作過一樣